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(FINAL) Chemistry Notebook 2016-17

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<strong>2016</strong>-<strong>17</strong> CHEMISTRY NOTEBOOK – LEONARDO GUTIERREZ


Honors <strong>Chemistry</strong><br />

Class Policies and Grading<br />

The students will receive a Unit Outline at the beginning of each Unit. It will<br />

have information about the assignments that they will do, what it’s grade<br />

classification will be, what action they will need to do to complete the<br />

assignment and when it is due.<br />

The students will receive a Weekly Memo of the activities they will be<br />

responsible for that week. It will serve to inform the students of the learning<br />

goal for the week. It will also give the students any special information<br />

about that week.<br />

The students will also receive daily lectures and assignments that are<br />

designed to teach and re-enforce information related to the learning goal.<br />

This will be time in which new material will be taught and reviewed and will<br />

give the students the opportunity to ask questions regarding the concepts<br />

being taught.<br />

The students will work with a Lab partner and also be in a Lab group, but it<br />

will be up to the individual student to do his or her part of all assignments<br />

and the individual student will ultimately be responsible for all information<br />

presented in the class.<br />

The students will be required to follow all District and School Policies and to<br />

follow all Lab Safety Procedures, which they will be given and will sign,<br />

while performing labs. Students should come to class on time and with the<br />

supplies needed for that class.<br />

The following grading policy will be used.<br />

Percent of Final Grade<br />

<strong>Notebook</strong> 40%<br />

Test/Projects 30%<br />

Labs/Quizzes 20%<br />

Work 10%<br />

The students will be given a teacher generated Mid Term and a District<br />

Final.


Unit 1<br />

Measurement Lab<br />

Separation of Mixtures Lab with Lab Write Up<br />

Unit 2<br />

Flame Test Lab<br />

Nuclear Decay Lab<br />

Element Marketing Project<br />

Unit 3<br />

Golden Penny Lab with Lab Write Up<br />

Molecular Geometry<br />

Research Presentation on a Chemical<br />

Mid Term<br />

Unit 4<br />

Double Displacement Lab<br />

Stoichiometry Lab with Lab Write Up<br />

Mole Educational Demonstration Project<br />

Unit 5<br />

Gas Laws Lab with Lab Write Up<br />

States of Matter Lab<br />

Teach a Gas Law Project<br />

Unit 6<br />

Dilutions Lab<br />

Titration Lab<br />

District Final


Unit 1 (22 days)<br />

Chapter 1 Introduction to <strong>Chemistry</strong><br />

Honors <strong>Chemistry</strong><br />

<strong>2016</strong>/20<strong>17</strong> Syllabus<br />

3 days<br />

1.1 The Scope of <strong>Chemistry</strong> 1.3 Thinking Like a Scientist<br />

1.2 <strong>Chemistry</strong> and You 1.4 Problem Solving in <strong>Chemistry</strong><br />

Chapter 2 Matter and Change<br />

2.1 Properties of Matter 2.3 Elements and Compounds<br />

2.2 Mixtures 2.4 Chemical Reactions<br />

Chapter 3 Scientific Measurement<br />

9 days<br />

10 days<br />

3.1 Using and Expressing Measurements 3.3 Solving Conversion Problems<br />

3.2 Units of Measurement<br />

Unit 2 (15 days)<br />

Chapter 4 Atomic Structure<br />

5 days<br />

4.1 Defining the Atom 4.3 Distinguishing Among Atoms<br />

4.2 Structure of the Nuclear Atom<br />

Chapter 5 Electrons in Atoms<br />

5 days<br />

5.1 Revising the Atomic Model 5.2 Electron Arrangement in Atoms<br />

5.3 Atomic Emission Spectrum and the Quantum Mechanical Model<br />

Chapter 6 The Periodic Table<br />

6.1 Organizing the Elements 6.3 Periodic Trends<br />

6.2 Classifying Elements<br />

Unit 3 (22 days)<br />

Chapter 25 Nuclear <strong>Chemistry</strong><br />

25.1 Nuclear Radiation 25.3 Fission and Fusion<br />

25.2 Nuclear Transformations 25.4 Radiation in Your Life<br />

Chapter 7 Ionic and Metallic Bonding<br />

7.1 Ions 7.3 Bonding in Metals<br />

7.2 Ionic Bonds and Ionic Compounds<br />

Chapter 8 Covalent Bonding<br />

5 days<br />

6 days<br />

8 days<br />

8 days<br />

8.1 Molecular Compounds 8.3 Bonding Theories<br />

8.2 The Nature of Covalent Bonding 8.4 Polar Bonds and Molecules<br />

Unit 4 (14 days)<br />

Chapter 9 Chemical Names and Formulas<br />

6 days<br />

9.1 Naming Ions 9.3 Naming & Writing Formulas Molecular Compounds<br />

9.2 Naming and Writing Formulas for Ionic Compounds 9.4 Names for Acids and Bases<br />

Chapter 22 Hydrocarbons Compounds<br />

22.1 Hydrocarbons 22.4 Hydrocarbon Rings<br />

Chapter 23 Functional Groups<br />

4 days<br />

4 days<br />

23.1 Introduction to Functional Groups 23.4 Alcohols, Ethers, and Amines<br />

2


Unit 5 (28 days)<br />

Chapter 10 Chemical Quantities 8 days<br />

10.1 The Mole: A Measurement of Matter 10.3 % Composition & Chem. Formulas<br />

10.2 Mole-Mass and Mole-Volume Relationships<br />

Chapter 11 Chemical Reactions 8 days<br />

11.1 Describing Chemical Reactions 11.3 Reactions in Aqueous Solutions<br />

11.2 Types of Chemical Reactions<br />

Chapter 12 Stoichiometry 12 days<br />

12.1 The Arithmetic of Equations 12.3 Limiting Reagent and % Yield<br />

12.2 Chemical Calculations<br />

Unit 6 (22 days)<br />

Chapter 13 States of Matter 6 days<br />

13.1 The Nature of Gases 13.3 The Nature of Solids<br />

13.2 The Nature of Liquids 13.4 Changes in State<br />

Chapter 14 The Behavior of Gases 10 days<br />

14.1 Properties of Gases 14.3 Ideal Gases<br />

14.2 The Gas Laws 14.4 Gases: Mixtures and Movement<br />

Chapter 15 Water and Aqueous Systems 6 days<br />

15.1 Water and its Properties 15.3 Heterogeneous Aqueous Systems<br />

15.2 Homogeneous Aqueous Systems<br />

Unit 7 (18 days)<br />

Chapter 16 Solutions 8 days<br />

16.1 Properties of Solutions 16.3 Colligative Properties of Solutions<br />

16.2 Concentrations of Solutions 16.4 Calc. Involving Colligative Property<br />

Chapter <strong>17</strong> Thermochemistry 5 days<br />

<strong>17</strong>.1 The Flow of Energy <strong>17</strong>.3 Heat in Changes of State<br />

<strong>17</strong>.2 Measuring and Expressing Enthalpy Change <strong>17</strong>.4 Calculating Heats in Reactions<br />

Chapter 18 Reaction Rates and Equilibrium 5 days<br />

18.1 Rates of Reactions 18.3 Reversible Reaction & Equilibrium<br />

18.2 The Progress of Chemical Reactions 18.5 Free Energy and Entropy<br />

Unit 8 (14 days)<br />

Chapter 19 Acid and Bases 10 days<br />

19.1 Acid-Base Theories 19.4 Neutralization Reactions<br />

19.2 Hydrogen Ions and Acidity 19.5 Salts in Solutions<br />

19.3 Strengths of Acids and Bases<br />

Chapter 20 Oxidation-Reduction Reactions 4 days<br />

20.1 The Meaning of Oxidation and Reduction 20.3 Describing Redox Equations<br />

20.2 Oxidation Numbers


Lorenzo Walker Technical High School<br />

MUSTANG LABORATORIES<br />

<strong>Chemistry</strong> Safety<br />

Safety in the MUSTANG LABORATORIES - <strong>Chemistry</strong> Laboratory<br />

Working in the chemistry laboratory is an interesting and rewarding experience. During your labs, you will be actively<br />

involved from beginning to end—from setting some change in motion to drawing some conclusion. In the laboratory, you<br />

will be working with equipment and materials that can cause injury if they are not handled properly.<br />

However, the laboratory is a safe place to work if you are careful. Accidents do not just happen; they are caused—by<br />

carelessness, haste, and disregard of safety rules and practices. Safety rules to be followed in the laboratory are listed<br />

below. Before beginning any lab work, read these rules, learn them, and follow them carefully.<br />

General<br />

1. Be prepared to work when you arrive at the lab. Familiarize yourself with the lab procedures before beginning the lab.<br />

2. Perform only those lab activities assigned by your teacher. Never do anything in the laboratory that is not called for in<br />

the laboratory procedure or by your teacher. Never work alone in the lab. Do not engage in any horseplay.<br />

3. Work areas should be kept clean and tidy at all times. Only lab manuals and notebooks should be brought to the work<br />

area. Other books, purses, brief cases, etc. should be left at your desk or placed in a designated storage area.<br />

4. Clothing should be appropriate for working in the lab. Jackets, ties, and other loose garments should be removed. Open<br />

shoes should not be worn.<br />

5. Long hair should be tied back or covered, especially in the vicinity of open flame.<br />

6. Jewelry that might present a safety hazard, such as dangling necklaces, chains, medallions, or bracelets should not be<br />

worn in the lab.<br />

7. Follow all instructions, both written and oral, carefully.<br />

8. Safety goggles and lab aprons should be worn at all times.<br />

9. Set up apparatus as described in the lab manual or by your teacher. Never use makeshift arrangements.<br />

10. Always use the prescribed instrument (tongs, test tube holder, forceps, etc.) for handling apparatus or equipment.<br />

11. Keep all combustible materials away from open flames.<br />

12. Never touch any substance in the lab unless specifically instructed to do so by your teacher.<br />

13. Never put your face near the mouth of a container that is holding chemicals.<br />

14. Never smell any chemicals unless instructed to do so by your teacher. When testing for odors, use a wafting motion to<br />

direct the odors to your nose.<br />

15. Any activity involving poisonous vapors should be conducted in the fume hood.<br />

16. Dispose of waste materials as instructed by your teacher.<br />

<strong>17</strong>. Clean up all spills immediately.<br />

18. Clean and wipe dry all work surfaces at the end of class. Wash your hands thoroughly.<br />

19. Know the location of emergency equipment (first aid kit, fire extinguisher, fire shower, fire blanket, etc.) and how to use them.<br />

20. Report all accidents to the teacher immediately.<br />

Handling Chemicals<br />

21. Read and double check labels on reagent bottles before removing any reagent. Take only as much reagent as you<br />

need.<br />

22. Do not return unused reagent to stock bottles.<br />

23. When transferring chemical reagents from one container to another, hold the containers out away from your body.<br />

24. When mixing an acid and water, always add the acid to the water.<br />

25. Avoid touching chemicals with your hands. If chemicals do come in contact with your hands, wash them immediately.<br />

26. Notify your teacher if you have any medical problems that might relate to lab work, such as allergies or asthma.<br />

27. If you will be working with chemicals in the lab, avoid wearing contact lenses. Change to glasses, if possible, or notify<br />

the teacher.<br />

Handling Glassware<br />

28. Glass tubing, especially long pieces, should be carried in a vertical position to minimize the likelihood of breakage and<br />

to avoid stabbing anyone.<br />

29. Never handle broken glass with your bare hands. Use a brush and dustpan to clean up broken glass. Dispose of the<br />

glass as directed by your teacher.


30. Always lubricate glassware (tubing, thistle tubes, thermometers, etc.) with water or glycerin before attempting to insert<br />

it into a rubber stopper.<br />

31. Never apply force when inserting or removing glassware from a stopper. Use a twisting motion. If a piece of glassware<br />

becomes "frozen" in a stopper, take it to your teacher.<br />

32. Do not place hot glassware directly on the lab table. Always use an insulating pad of some sort.<br />

33. Allow plenty of time for hot glass to cool before touching it. Hot glass can cause painful burns. (Hot glass looks cool.)<br />

Heating Substances<br />

34. Exercise extreme caution when using a gas burner. Keep your head and clothing away from the flame.<br />

35. Always turn the burner off when it is not in use.<br />

36. Do not bring any substance into contact with a flame unless instructed to do so.<br />

37. Never heat anything without being instructed to do so.<br />

38. Never look into a container that is being heated.<br />

39. When heating a substance in a test tube, make sure that the mouth of the tube is not pointed at yourself or anyone<br />

else.<br />

40. Never leave unattended anything that is being heated or is visibly reacting.<br />

First Aid in the MUSTANG LABORATORIES - <strong>Chemistry</strong> Laboratory<br />

Accidents do not often happen in well-equipped chemistry laboratories if students understand safe laboratory procedures<br />

and are careful in following them. When an occasional accident does occur, it is likely to be a minor one.<br />

The instructor will assist in treating injuries such as minor cuts and burns. However, for some types of injuries, you must<br />

take action immediately. The following information will be helpful to you if an accident occurs.<br />

1. Shock. People who are suffering from any severe injury (for example, a bad burn or major loss of blood) may be in a<br />

state of shock. A person in shock is usually pale and faint. The person may be sweating, with cold, moist skin and a weak,<br />

rapid pulse. Shock is a serious medical condition. Do not allow a person in shock to walk anywhere—even to the campus<br />

security office. While emergency help is being summoned, place the victim face up in a horizontal position, with the feet<br />

raised about 30 centimeters. Loosen any tightly fitting clothing and keep him or her warm.<br />

2. Chemicals in the Eyes. Getting any kind of a chemical into the eyes is undesirable, but certain chemicals are<br />

especially harmful. They can destroy eyesight in a matter of seconds. Because you will be wearing safety goggles at all<br />

times in the lab, the likelihood of this kind of accident is remote. However, if it does happen, flush your eyes with water<br />

immediately. Do NOT attempt to go to the campus office before flushing your eyes. It is important that flushing with water<br />

be continued for a prolonged time—about 15 minutes.<br />

3. Clothing or Hair on Fire. A person whose clothing or hair catches on fire will often run around hysterically in an<br />

unsuccessful effort to get away from the fire. This only provides the fire with more oxygen and makes it burn faster. For<br />

clothing fires, throw yourself to the ground and roll around to extinguish the flames. For hair fires, use a fire blanket to<br />

smother the flames. Notify campus security immediately.<br />

4. Bleeding from a Cut. Most cuts that occur in the chemistry laboratory are minor. For minor cuts, apply pressure to the<br />

wound with a sterile gauze. Notify campus security of all injuries in the lab. If the victim is bleeding badly, raise the<br />

bleeding part, if possible, and apply pressure to the wound with a piece of sterile gauze. While first aid is being given,<br />

someone else should notify the campus security officer.<br />

5. Chemicals in the Mouth. Many chemicals are poisonous to varying degrees. Any chemical taken into the mouth<br />

should be spat out and the mouth rinsed thoroughly with water. Note the name of the chemical and notify the campus<br />

office immediately. If the victim swallows a chemical, note the name of the chemical and notify campus security<br />

immediately.<br />

If necessary, the campus security officer or administrator will contact the Poison Control Center, a hospital emergency<br />

room, or a physician for instructions.<br />

6. Acid or Base Spilled on the Skin.<br />

Flush the skin with water for about 15 minutes. Take the victim to the campus office to report the injury.<br />

7. Breathing Smoke or Chemical Fumes.<br />

All experiments that give off smoke or noxious gases should be conducted in a well-ventilated fume hood. This will make<br />

an accident of this kind unlikely. If smoke or chemical fumes are present in the laboratory, all persons—even those who<br />

do not feel ill—should leave the laboratory immediately. Make certain that all doors to the laboratory are closed after the<br />

last person has left. Since smoke rises, stay low while evacuating a smoke-filled room. Notify campus security<br />

immediately.


MUSTANG LABORATORIES<br />

COMMITMENT TO SAFETY IN THE LABORATORY<br />

As a student enrolled in <strong>Chemistry</strong> at Lorenzo Walker Technical High<br />

School, I agree to use good laboratory safety practices at all times. I<br />

also agree that I will:<br />

1. Conduct myself in a professional manner, respecting both my personal safety and the safety of<br />

others in the laboratory.<br />

2. Wear proper and approved safety glasses or goggles in the laboratory at all times.<br />

3. Wear sensible clothing and tie back long hair in the laboratory. Understand that open-toed shoes<br />

pose a hazard during laboratory classes and that contact lenses are an added safety risk.<br />

4. Keep my lab area free of clutter during an experiment.<br />

5. Never bring food or drink into the laboratory, nor apply makeup within the laboratory.<br />

6. Be aware of the location of safety equipment such as the fire extinguisher, eye wash station, fire<br />

blanket, first aid kit. Know the location of the nearest telephone and exits.<br />

7. Read the assigned lab prior to coming to the laboratory.<br />

8. Carefully read all labels on all chemical containers before using their contents, remove a small<br />

amount of reagent properly if needed, do not pour back the unused chemicals into the original<br />

container.<br />

9. Dispose of chemicals as directed by the instructor only. At no time will I pour anything down the<br />

sink without prior instruction.<br />

10. Never inhale fumes emitted during an experiment. Use the fume hood when instructed to do so.<br />

11. Report any accident immediately to the instructor, including chemical spills.<br />

12. Dispose of broken glass and sharps only in the designated containers.<br />

13. Clean my work area and all glassware before leaving the laboratory.<br />

14. Wash my hands before leaving the laboratory.<br />

NAME __________________________<br />

Leonardo Gutierrez<br />

Diana Gutierrez<br />

PARENT NAME ____________________________<br />

2 (239)-810-6036<br />

PERIOD ________________________ PARENT NUMBER _________________________<br />

SIGNATURE ____________________________<br />

DATE ____________________________________<br />

8-25-<strong>2016</strong><br />

6


8<br />

Chapter 1<br />

Unit 1<br />

Introduction to <strong>Chemistry</strong><br />

The students will learn why and how to solve problems using<br />

chemistry.<br />

Identify what is science, what clearly is not science, and what superficially<br />

resembles science (but fails to meet the criteria for science).<br />

Students will identify a phenomenon as science or not science.<br />

Science<br />

Observation<br />

Inference<br />

Hypothesis<br />

Identify which questions can be answered through science and which<br />

questions are outside the boundaries of scientific investigation, such as<br />

questions addressed by other ways of knowing, such as art, philosophy, and<br />

religion.<br />

Students will differentiate between problems and/or phenomenon that can and<br />

those that cannot be explained or answered by science.<br />

Students will differentiate between problems and/or phenomenon that can and<br />

those that cannot be explained or answered by science.<br />

Observation<br />

Inference<br />

Hypothesis<br />

Theory<br />

Controlled experiment<br />

Describe how scientific inferences are drawn from scientific observations<br />

and provide examples from the content being studied.<br />

Students will conduct and record observations.<br />

Students will make inferences.<br />

Students will identify a statement as being either an observation or inference.<br />

Students will pose scientific questions and make predictions based on<br />

inferences.<br />

Inference<br />

Observation<br />

Hypothesis<br />

Controlled experiment<br />

Identify sources of information and assess their reliability according to the<br />

strict standards of scientific investigation.<br />

Students will compare and assess the validity of known scientific information<br />

from a variety of sources:


Print vs. print<br />

Online vs. online<br />

Print vs. online<br />

Students will conduct an experiment using the scientific method and compare<br />

with other groups.<br />

Controlled experiment<br />

Investigation<br />

Peer Review<br />

Accuracy<br />

Precision<br />

Percentage Error<br />

Chapter 2<br />

Matter and Change<br />

The students will learn what properties are used to describe<br />

matter and how matter can change its form.<br />

Differentiate between physical and chemical properties and physical and<br />

chemical changes of matter.<br />

Students will be able to identify physical and chemical properties of various<br />

substances.<br />

Students will be able to identify indicators of physical and chemical changes.<br />

Students will be able to calculate density.<br />

mass<br />

physical property<br />

volume<br />

chemical property<br />

vapor<br />

extensive property<br />

Chapter 3<br />

mixture<br />

intensive property<br />

solution<br />

element<br />

compound<br />

Scientific Measurements<br />

The students will be able to solve conversion problems using<br />

measurements.<br />

Determine appropriate and consistent standards of measurement for the<br />

data to be collected in a survey or experiment.<br />

Students will participate in activities to collect data using standardized<br />

measurement.<br />

Students will be able to manipulate/convert data collected and apply the data<br />

to scientific situations.<br />

Scientific notation<br />

International System of Units (SI)<br />

Significant figures<br />

Accepted value<br />

Experimental value<br />

Percent error<br />

Dimensional analysis


To use the Stair-Step method, find the prefix the original measurement starts with. (ex. milligram)<br />

If there is no prefix, then you are starting with a base unit.<br />

Find the step which you wish to make the conversion to. (ex. decigram)<br />

Count the number of steps you moved, and determine in which direction you moved (left or right).<br />

The decimal in your original measurement moves the same number of places as steps you moved and in the<br />

same direction. (ex. milligram to decigram is 2 steps to the left, so 40 milligrams = .40 decigrams)<br />

If the number of steps you move is larger than the number you have, you will have to add zeros to hold the<br />

places. (ex. kilometers to meters is three steps to the right, so 10 kilometers would be equal to 10,000 m)<br />

That’s all there is to it! You need to be able to count to 6, and know your left from your right!<br />

1) Write the equivalent<br />

a) 5 dm =_______m b) 4 mL = ______L c) 8 g = _______mg<br />

d) 9 mg =_______g e) 2 mL = ______L f) 6 kg = _____g<br />

g) 4 cm =_______m h) 12 mg = ______ g i) 6.5 cm 3 = _______L<br />

j) 7.02 mL =_____cm 3 k) .03 hg = _______ dg l) 6035 mm _____cm<br />

m) .32 m = _______cm n) 38.2 g = _____kg


12<br />

2. One cereal bar has a mass of 37 g. What is the mass of 6 cereal bars? Is that more than or less<br />

than 1 kg? Explain your answer.<br />

3. Wanda needs to move 110 kg of rocks. She can carry l0 hg each trip. How many trips must she<br />

make? Explain your answer.<br />

4. Dr. O is playing in her garden again She needs 1 kg of potting soil for her plants. She has 750 g.<br />

How much more does she need? Explain your answer.<br />

5. Weather satellites orbit Earth at an altitude of 1,400,000 meters. What is this altitude in kilometers?<br />

6. Which unit would you use to measure the capacity? Write milliliter or liter.<br />

a) a bucket __________<br />

b) a thimble __________<br />

c) a water storage tank__________<br />

d) a carton of juice__________<br />

7. Circle the more reasonable measure:<br />

a) length of an ant 5mm or 5cm<br />

b) length of an automobile 5 m or 50 m<br />

c) distance from NY to LA 450 km or 4,500 km<br />

d) height of a dining table 75 mm or 75 cm<br />

8. Will a tablecloth that is 155 cm long cover a table that is 1.6 m long? Explain your answer.<br />

9. A dollar bill is 15.6 cm long. If 200 dollar bills were laid end to end, how many meters long would<br />

the line be?<br />

10. The ceiling in Jan’s living room is 2.5 m high. She has a hanging lamp that hangs down 41 cm.<br />

Her husband is exactly 2 m tall. Will he hit his head on the hanging lamp? Why or why not?


Using SI Units<br />

Match the terms in Column II with the descriptions in Column I. Write the letters of the correct term in<br />

the blank on the left.<br />

Column I Column II<br />

_____ 1. distance between two points<br />

a. time<br />

_____ 2. SI unit of length<br />

_____ 3. tool used to measure length<br />

_____ 4. units obtained by combining other units<br />

_____ 5. amount of space occupied by an object<br />

_____ 6. unit used to express volume<br />

_____ 7. SI unit of mass<br />

_____ 8. amount of matter in an object<br />

_____ 9. mass per unit of volume<br />

_____ 10. temperature scale of most laboratory thermometers<br />

_____ 11. instrument used to measure mass<br />

_____ 12. interval between two events<br />

_____ 13. SI unit of temperature<br />

_____ 14. SI unit of time<br />

_____ 15. instrument used to measure temperature<br />

b. volume<br />

c. mass<br />

d. density<br />

e. meter<br />

f. kilogram<br />

g. derived<br />

h. liter<br />

i. second<br />

j. Kelvin<br />

k. length<br />

1. balance<br />

m. meterstick<br />

n. thermometer<br />

o. Celsius<br />

Circle the two terms in each group that are related. Explain how the terms are related.<br />

16. Celsius degree, mass, Kelvin _____________________________________________________<br />

________________________________________________________________________________<br />

<strong>17</strong>. balance, second, mass __________________________________________________________<br />

________________________________________________________________________________<br />

18. kilogram, liter, cubic centimeter __________________________________________________<br />

________________________________________________________________________________<br />

19. time, second, distance __________________________________________________________<br />

________________________________________________________________________________<br />

20. decimeter, kilometer, Kelvin _____________________________________________________<br />

________________________________________________________________________________


1. How many meters are in one kilometer? __________<br />

2. What part of a liter is one milliliter? __________<br />

3. How many grams are in two dekagrams? __________<br />

4. If one gram of water has a volume of one milliliter, what would the mass of one liter of water be in<br />

kilograms?__________<br />

5. What part of a meter is a decimeter? __________<br />

In the blank at the left, write the term that correctly completes each statement. Choose from the terms<br />

listed below.<br />

Metric SI standard ten<br />

prefixes ten tenth<br />

6. An exact quantity that people agree to use for comparison is a ______________ standard ten .<br />

7. The system of measurement used worldwide in science is _______________ .<br />

8. SI is based on units of _______________ .<br />

9. The system of measurement that was based on units of ten was the _______________ system.<br />

10. In SI, _______________ prefixes are used with the names of the base unit to indicate the multiple of ten<br />

that is being used with the base unit.<br />

11. The prefix deci- means _______________ ten<br />

.<br />

14


Standards of Measurement<br />

Fill in the missing information in the table below.<br />

Prefix<br />

S.I prefixes and their meanings<br />

Meaning<br />

milli<br />

0.001<br />

centi<br />

0.01<br />

deci- 0.1<br />

deca<br />

10<br />

hecto- 100<br />

kilo<br />

1000<br />

Circle the larger unit in each pair of units.<br />

1. millimeter, kilometer 4. centimeter, millimeter<br />

2. decimeter, dekameter 5. hectogram, kilogram<br />

3. hectogram, decigram<br />

6. In SI, the base unit of length is the meter. Use this information to arrange the following units of<br />

measurement in the correct order from smallest to largest.<br />

Write the number 1 (smallest) through 7 - (largest) in the spaces provided.<br />

_____ 7 a. kilometer<br />

_____ 2 b. centimeter<br />

_____ 4 c. meter<br />

_____ 6 e. hectometer<br />

_____ 1 f. millimeter<br />

_____ 3 g. decimeter<br />

_____ 5 d. dekameter<br />

Use your knowledge of the prefixes used in SI to answer the following questions in the spaces<br />

provided.<br />

7. One part of the Olympic games involves an activity called the decathlon. How many events do you<br />

think make up the decathlon?_____________________________________________________<br />

10<br />

8. How many years make up a decade? _______________________________________________<br />

10<br />

9. How many years make up a century? ______________________________________________<br />

100<br />

10. What part of a second do you think a millisecond is? __________________________________<br />

.001


The Learning Goal for this assignment is:<br />

Notes Section<br />

1. 7,485 6. 1.683<br />

2. 884.2 7. 3.622<br />

3. 0.00002887 8. 0.0000<strong>17</strong>35<br />

4. 0.05893 9. 0.9736<br />

5. 0.006162 10. 0.08558<br />

11. 6.633 X 10−⁴ 16. 1.937 X 10⁴<br />

12. 4.445 X 10−⁴ <strong>17</strong>. 3.457 X 10⁴<br />

13. 2.182 X 10−³ 18. 3.948 X 10−⁵<br />

14. 4.695 X 10² 19. 8.945 X 10⁵<br />

15. 7.274 X 10⁵ 20. 6.783 X 10²<br />

16


SCIENTIFIC NOTATION RULES<br />

How to Write Numbers in Scientific Notation<br />

Scientific notation is a standard way of writing very large and very small numbers so that they're<br />

easier to both compare and use in computations. To write in scientific notation, follow the form<br />

N X 10 ᴬ<br />

where N is a number between 1 and 10, but not 10 itself, and A is an integer (positive or negative<br />

number).<br />

RULE #1: Standard Scientific Notation is a number from 1 to 9 followed by a decimal and the<br />

remaining significant figures and an exponent of 10 to hold place value.<br />

Example:<br />

5.43 x 10 2 = 5.43 x 100 = 543<br />

8.65 x 10 – 3 = 8.65 x .001 = 0.00865<br />

****54.3 x 10 1 is not Standard Scientific Notation!!!<br />

RULE #2: When the decimal is moved to the Left the exponent gets Larger, but the value of the<br />

number stays the same. Each place the decimal moves Changes the exponent by one (1). If you<br />

move the decimal to the Right it makes the exponent smaller by one (1) for each place it is moved.<br />

Example:<br />

6000. x 10 0 = 600.0 x 10 1 = 60.00 x 10 2 = 6.000 x 10 3 = 6000<br />

(Note: 10 0 = 1)<br />

All the previous numbers are equal, but only 6.000 x 10 3 is in proper Scientific Notation.


RULE #3: To add/subtract in scientific notation, the exponents must first be the same.<br />

Example:<br />

(3.0 x 10 2 ) + (6.4 x 10 3 ); since 6.4 x 10 3 is equal to 64. x 10 2 . Now add.<br />

(3.0 x 10 2 )<br />

+ (64. x 10 2 )<br />

67.0 x 10 2 = 6.70 x 10 3 = 6.7 x 10 3<br />

67.0 x 10 2 is mathematically correct, but a number in standard scientific notation can only<br />

have one number to the left of the decimal, so the decimal is moved to the left one place and<br />

one is added to the exponent.<br />

Following the rules for significant figures, the answer becomes 6.7 x 10 3 .<br />

RULE #4: To multiply, find the product of the numbers, then add the exponents.<br />

Example:<br />

(2.4 x 10 2 ) (5.5 x 10 –4 ) = ? [2.4 x 5.5 = 13.2]; [2 + -4 = -2], so<br />

(2.4 x 10 2 ) (5.5 x 10 –4 ) = 13.2 x 10 –2 = 1.3 x 10 – 1<br />

RULE #5: To divide, find the quotient of the number and subtract the exponents.<br />

Example:<br />

(3.3 x 10 – 6 ) / (9.1 x 10 – 8 ) = ? [3.3 / 9.1 = .36]; [-6 – (-8) = 2], so<br />

(3.3 x 10 – 6 ) / (9.1 x 10 – 8 ) = .36 x 10 2 = 3.6 x 10 1<br />

18


Convert each number from Scientific Notation to real numbers:<br />

1. 7.485 X 10³ 7,485 6. 1.683 X 10⁰ 1<br />

2. 8.842 X 10² 884.2 7. 3.622 10⁰ 1<br />

3. 2.887 X 10−⁵ 0.00002887 8. 1.735 X 10−⁵ 0.0000<strong>17</strong>35<br />

4. 5.893 X 10−² 0.05893 9. 9.736 X 10−¹ 0.9736<br />

5. 6.162 X 10−³ 0.006162 10. 8.558 X 10−² 0.08558<br />

Convert each number from a real number to Scientific Notation:<br />

11. 0.0006633 6.633 x 10^4 16. 1,937,000 1.937 x 10^-6<br />

12. 0.0004445 4.445 x 10^4 <strong>17</strong>. 34,570 3.457 x 10^-4<br />

13. 0.002182 2.182 x 10^3 18. 0.00003948 3.948 x 10^5<br />

14. 469.5 4.695 x 10^4.695 19. 894,500 8.945 x 10^-5<br />

15. 727,400 7.274 x 10^-5 20. 678.3 6.783 x 10^-2


The Learning Goal for this assignment is:<br />

Notes Section:<br />

Question Sig Figs Question Add & Subtract Question Multiple & Divide<br />

1 4 1 55.36 1 20,000<br />

2 4 2 84.2 2 94<br />

3 3 3 115.4 3 300<br />

4 3 4 0.8 4 7<br />

5 4 5 245.53 5 62<br />

6 3 6 34.5 6 0.005<br />

7 3 7 74.0 7 4,000<br />

8 2 8 53.287 8 3,900,000<br />

9 2 9 54.876 9 2<br />

10 2 10 40.19 10 30,000,000<br />

11 3 11 7.7 11 1,200<br />

12 2 12 67.<strong>17</strong>0 12 0.2<br />

13 3 13 81.0 13 0.87<br />

14 4 14 73.290 14 0.049<br />

15 4 15 29.789 15 2,000<br />

16 3 16 39.53 16 0.5<br />

<strong>17</strong> 4 <strong>17</strong> 70.58 <strong>17</strong> 1.9<br />

18 2 18 86.6 18 0.05<br />

19 2 19 64.990 19 230<br />

20 1 20 36.0 20 460,000<br />

20


Significant Figures Rules<br />

There are three rules on determining how many significant figures are in a<br />

number:<br />

1. Non-zero digits are always significant.<br />

2. Any zeros between two significant digits are significant.<br />

3. A final zero or trailing zeros in the DECIMAL PORTION ONLY are<br />

significant.<br />

Please remember that, in science, all numbers are based upon measurements (except for a very few<br />

that are defined). Since all measurements are uncertain, we must only use those numbers that are<br />

meaningful.<br />

Not all of the digits have meaning (significance) and, therefore, should not be written down. In<br />

science, only the numbers that have significance (derived from measurement) are written.<br />

Rule 1: Non-zero digits are always significant.<br />

If you measure something and the device you use (ruler, thermometer, triple-beam, balance, etc.)<br />

returns a number to you, then you have made a measurement decision and that ACT of measuring<br />

gives significance to that particular numeral (or digit) in the overall value you obtain.<br />

Hence a number like 46.78 would have four significant figures and 3.94 would have three.<br />

Rule 2: Any zeros between two significant digits are significant.<br />

Suppose you had a number like 409. By the first rule, the 4 and the 9 are significant. However, to<br />

make a measurement decision on the 4 (in the hundred's place) and the 9 (in the one's place), you<br />

HAD to have made a decision on the ten's place. The measurement scale for this number would have<br />

hundreds, tens, and ones marked.<br />

Like the following example:<br />

These are sometimes called "captured zeros."<br />

If a number has a decimal at the end (after the one’s place) then all digits (numbers) are significant<br />

and will be counted.<br />

In the following example the zeros are significant digits and highlighted in blue.<br />

960.<br />

70050.


Rule 3: A final zero or trailing zeros in the decimal portion ONLY are<br />

significant.<br />

This rule causes the most confusion among students.<br />

In the following example the zeros are significant digits and highlighted in blue.<br />

0.07030<br />

0.00800<br />

Here are two more examples where the significant zeros are highlighted in blue.<br />

When Zeros are Not Significant Digits<br />

4.7 0 x 10−³<br />

6.5 0 0 x 10⁴<br />

22<br />

Zero Type # 1 : Space holding zeros in numbers less than one.<br />

In the following example the zeros are NOT significant digits and highlighted in red.<br />

0.09060<br />

0.00400<br />

These zeros serve only as space holders. They are there to put the decimal point in its correct<br />

location.<br />

They DO NOT involve measurement decisions.<br />

Zero Type # 2 : Trailing zeros in a whole number.<br />

In the following example the zeros are NOT significant digits and highlighted in red.<br />

200<br />

25000<br />

For addition and subtraction, look at the decimal portion (i.e., to the right of the decimal point)<br />

of the numbers ONLY. Here is what to do:<br />

1) Count the number of significant figures in the decimal portion of each number in the problem. (The<br />

digits to the left of the decimal place are not used to determine the number of decimal places in the<br />

final answer.)<br />

2) Add or subtract in the normal fashion.<br />

3) Round the answer to the LEAST number of places in the decimal portion of any number in the<br />

problem<br />

The following rule applies for multiplication and division:<br />

The LEAST number of significant figures in any number of the problem determines the number of<br />

significant figures in the answer.<br />

This means you MUST know how to recognize significant figures in order to use this rule.


How Many Significant Digits for Each Number?<br />

1) 2359 = ______ 4<br />

2) 2.445 x 10−⁵= ______ 4<br />

3) 2.93 x 10⁴= ______ 3<br />

4) 1.30 x 10−⁷= ______ 3<br />

5) 2604 = ______ 4<br />

6) 9160 = ______ 3<br />

7) 0.0800 = ______ 3<br />

8) 0.84 = ______ 2<br />

9) 0.0080 = ______ 2<br />

10) 0.00040 = ______ 2<br />

11) 0.0520 = ______ 3<br />

12) 0.060 = ______ 2<br />

13) 6.90 x 10−¹= ______ 3<br />

14) 7.200 x 10⁵= ______ 4<br />

15) 5.566 x 10−²= ______ 4<br />

16) 3.88 x 10⁸= ______ 3<br />

<strong>17</strong>) 3004 = ______ 4<br />

18) 0.021 = ______ 2<br />

19) 240 = ______ 2<br />

20) 500 = ______ 1


For addition and subtraction, look at the decimal portion (i.e., to the right of the decimal point) of the<br />

numbers ONLY. Here is what to do:<br />

1) Count the number of significant figures in the decimal portion of each number in the problem. (The<br />

digits to the left of the decimal place are not used to determine the number of decimal places in the<br />

final answer.)<br />

2) Add or subtract in the normal fashion.<br />

3) Round the answer to the LEAST number of places in the decimal portion of any number in the<br />

problem.<br />

Solve the Problems and Round Accordingly...<br />

1) 43.287 + 5.79 + 6.284 = _______ 55.36<br />

2) 87.54 - 3.3 = _______ 84.2<br />

3) 99.1498 + 6.5397 + 9.7 = _______ 115.4<br />

4) 5.868 - 5.1 = _______ 0.8<br />

5) 59.9233 + 86.21 + 99.396 = _______ 245.53<br />

6) 7.7 + 26.756 = _______ 34.5<br />

7) 66.8 + 2.3 + 4.8516 = _______ 72.0<br />

8) 9.7419 + 43.545 = _______ 53.287<br />

9) 4.8976 + 48.4644 + 1.514 = _______ 54.876<br />

10) 4.335 + 35.85 = _______ 40.19<br />

11) 9.448 - 1.7 = _______ 7.7<br />

12) 75.826 - 8.6555 = _______ 66.961<br />

13) 57.2 + 23.814 = _______ 81<br />

14) 77.684 - 4.394 = _______ 73.29<br />

15) 26.4496 + 3.339 = _______ 29.789<br />

16) 9.6848 + 29.85 = _______ 39.53<br />

<strong>17</strong>) 63.11 + 2.5412 + 4.93 = _______ 70.58<br />

18) 11.2471 + 75.4 = _______ 86.6<br />

19) 73.745 - 8.755 = _______ 64.99<br />

20) 6.5238 + 1.7 + 27.79 = _______ 36.01<br />

24


The following rule applies for multiplication and division:<br />

The LEAST number of significant figures in any number of the problem determines the number of<br />

significant figures in the answer.<br />

This means you MUST know how to recognize significant figures in order to use this rule.<br />

Solve the Problems and Round Accordingly...<br />

1) 0.6 x 65.0 x 602 = __________<br />

20,000<br />

2) 720 ÷ 7.7 = __________<br />

94<br />

3) 929 x 0.3 = __________<br />

300<br />

4) 300 ÷ 44.31 = __________<br />

6.770<br />

5) 608 ÷ 9.8 = __________<br />

62.0<br />

6) 0.06 x 0.079 = __________<br />

.0050<br />

7) 0.008 x 72.91 x 7000 = __________<br />

4082<br />

8) 73.94 x 67 x 780 = __________<br />

3,864,000<br />

9) 0.62 x 0.097 x 40 = __________<br />

2.4<br />

10) 600 x 10 x 5030 = __________<br />

30,200,000<br />

11) 5200 ÷ 4.46 = __________<br />

1<strong>17</strong>0<br />

12) 0.0052 x 0.4 x 107 = __________<br />

.226<br />

13) 0.099 x 8.8 = __________<br />

.87<br />

14) 0.0095 x 5.2 = __________<br />

.049<br />

15) 8000 ÷ 4.62 = __________<br />

<strong>17</strong>30<br />

16) 0.6 x 0.8 = __________<br />

.5<br />

<strong>17</strong>) 2.84 x 0.66 = __________<br />

1.87<br />

18) 0.5 x 0.09 = __________<br />

0.05<br />

19) 8100 ÷ 34.84 = __________<br />

232.5<br />

20) 8.24 x 6.9 x 8100 = __________<br />

461,000


Dimensional Analysis<br />

This is a way to convert from one unit of a given substance to<br />

another unit using ratios or conversion units. What this video<br />

www.youtube.com/watch?v=aZ3J60GYo6U<br />

Let’ look at a couple of examples:<br />

1. Convert 2.6 qt to mL.<br />

First we need a ratio or conversion unit so that we can go from quarts to milliliters. 1.00 qt = 946 mL<br />

Next write down what you are starting with<br />

2.6 qt<br />

Then make you conversion tree<br />

2.6 qt<br />

Then fill in the units in your ratio so that you can cancel out the original unit and will be left with the<br />

unit you need for the answer. Cross out units, one at a time that are paired, and one on top one on<br />

the bottom.<br />

2.6 qt mL<br />

qt<br />

Now fill in the values from the ratio.<br />

2.6 qt 946 mL<br />

1.00 qt<br />

Now multiply all numbers on the top and multiply all numbers on the bottom and write them as a<br />

fraction.<br />

2.6 qt 946 mL = 2,459.6 mL<br />

1.00 qt 1.00<br />

Now divide the top number by the bottom number and write that number with the unit that was not<br />

crossed out.<br />

26


1qt=32 oz 1gal = 4qts 1.00 qt = 946 mL 1L = 1000mL<br />

2. Convert 8135.6 mL to quarts<br />

=<br />

3. Convert 115.2 oz to mL<br />

=<br />

4. Convert 2.3 g to Liters<br />

=<br />

5. Convert 8.42 L to oz<br />

=<br />

Go to http://science.widener.edu/svb/tutorial/ chose #7 “Converting Volume” and do 5 more in the<br />

space provided.<br />

1. Convert _________ to _________<br />

=<br />

2. Convert _________ to _________<br />

=<br />

3. Convert _________ 2.<strong>17</strong> g to _________ liters<br />

2.<strong>17</strong> g 4 qts<br />

946 mL<br />

1 g<br />

1 qt<br />

1000 mL<br />

=<br />

1 L 8.21128 L<br />

8.21 L<br />

4. Convert _________ 7.5 qts to _________<br />

liters<br />

7.5 qts 946 mL<br />

1 qt<br />

1000 mL<br />

5. Convert _________ 0.3 gallons to _________ milliliters<br />

0.3 gallons 4 qts<br />

1 gallon<br />

1 L 7.095 L<br />

946 mL 1135.2 mL<br />

1 qt<br />

=<br />

=<br />

7.1L<br />

1135 mL


Chapter 4<br />

Unit 2<br />

Atomic Structure<br />

The students will learn what makes up atoms and how are<br />

atoms of one element different from atoms of another element.<br />

Explore the scientific theory of atoms (also known as atomic theory) by<br />

describing changes in the atomic model over time and why those changes<br />

were necessitated by experimental evidence.<br />

Students will be able to draw/identify each atomic model.<br />

Students will be able to compare/contrast the different atomic models.<br />

Students will be able to describe how results of experimental evidence caused<br />

the atomic model to change.<br />

Proton<br />

Electron<br />

Neutron<br />

Nucleus<br />

electron cloud<br />

Explore the scientific theory of atoms (also known as atomic theory) by<br />

describing the structure of atoms in terms of protons, neutrons and<br />

electrons, and differentiate among these particles in terms of their mass,<br />

electrical charges and locations within the atom.<br />

Students will compare/contrast the characteristics of subatomic particles.<br />

atomic number<br />

mass number<br />

isotope<br />

atomic mass unit (amu)<br />

atomic mass<br />

28


Chapter 5<br />

Electrons in Atoms<br />

The students will be able to describe the arrangement of<br />

electrons in atoms and predict what will happen when<br />

electrons in atoms absorb or release energy.<br />

Describe the quantization of energy at the atomic level.<br />

Students will participate in activities to view emission spectrums using a<br />

diffraction grating or a spectroscope.<br />

Students will be able to explain how the spectrum lines relate to electron motion.<br />

energy level<br />

atomic orbital<br />

quantum mechanical model<br />

Chapter 6<br />

The Periodic Table<br />

The student will learn what information the periodic table<br />

provides and how periodic trends can be explained.<br />

Relate properties of atoms and their position in the periodic table to the<br />

arrangement of their electrons.<br />

Students will be able to compare and contrast metals, nonmetals, and metalloids.<br />

Students will be able to describe the traits of various families on the periodic<br />

table.<br />

Students will be able to explain periodicity.<br />

Students will write/represent electron configuration of various elements.<br />

Students will be able to use a periodic table to calculate the number of p + , e - , and<br />

n 0 .<br />

Students will be able to calculate the average weight of mass.<br />

periodic law<br />

halogen<br />

metals<br />

noble gas<br />

nonmetals<br />

transition metal<br />

metalloid<br />

atomic radius<br />

alkali metal<br />

ionization energy<br />

alkaline earth metal<br />

electronegativity


The Learning Goal for this assignment is:<br />

The students will learn what makes up atoms and how are atoms of one element different from<br />

atoms of another element.<br />

Notes Section<br />

Smaller Than Atoms?<br />

-Atoms make up all matter<br />

-Subatomic particles include the electron, proton, and neutron<br />

-Protons and neutrons mak up the nucleus, and electrons float around the nucleus in orbitals<br />

-Electrons are negative (-), protons are poitive (+), and neutrons have no charge (0)<br />

-If there are more or less electrons than protons, that atom is an ion.<br />

Looking at Ions<br />

-Normal atoms have a neutral charge<br />

-Atoms want full valence shells, so they will lose or gain electrons to complete them, making an ion<br />

-Positive ions are called cations and negative ions are anions<br />

-Once atoms have full valence shells, they'll have a positive or negative charge, and will bond with<br />

atoms of the opposite charge<br />

-There are covalent and ionic bonds<br />

-Ionic bonds are groups of charged electrons held together by electrical froces, but are easily broken by<br />

outside electrical forces, and very weak in water.<br />

Atomic Mass<br />

-An isotope is an atom with an extra or missing neutron<br />

-Electrons have a barely noticable mass compared to protons and neutrons<br />

-Atomic mass is the average mass of the element, including the average of all the isotopes<br />

http://www.learner.org/interactives/periodic/basics_interactive.html<br />

30


Atoms Are Building Blocks<br />

Atoms are the basis of chemistry. They are the basis for everything in the Universe. You<br />

should start by remembering that matter is composed of atoms. Atoms and the study of<br />

atoms are a world unto themselves. We're going to cover basics like atomic structure<br />

and bonding between atoms.<br />

Smaller Than Atoms?<br />

Are there pieces of matter that are smaller than atoms?<br />

Sure there are. You'll soon be learning that atoms are<br />

composed of pieces like electrons, protons, and neutrons.<br />

But guess what? There are even smaller particles moving<br />

around in atoms. These super-small particles can be found<br />

inside the protons and neutrons. Scientists have many<br />

names for those pieces, but you may have heard of<br />

nucleons and quarks. Nuclear chemists and physicists<br />

work together at particle accelerators to discover the<br />

presence of these tiny, tiny, tiny pieces of matter.<br />

Even though super-tiny atomic particles exist, you only<br />

need to remember the three basic parts of an atom: electrons, protons, and neutrons.<br />

What are electrons, protons, and neutrons? A picture works best to show off the idea.<br />

You have a basic atom. There are three types of pieces in that atom: electrons, protons,<br />

and neutrons. That's all you have to remember. Three things! As you know, there are<br />

almost 120 known elements in the periodic table. Chemists and physicists haven't<br />

stopped there. They are trying to make new ones in labs every day. The thing that<br />

makes each of those elements different is the number of electrons, protons, and<br />

neutrons. The protons and neutrons are always in the center of the atom. Scientists call<br />

the center region of the atom the nucleus. The nucleus in<br />

a cell is a thing. The nucleus in an atom is a place where<br />

you find protons and neutrons. The electrons are always<br />

found whizzing around the center in areas called shells or<br />

orbitals.<br />

You can also see that each piece has either a "+", "-", or a<br />

"0." That symbol refers to the charge of the particle. Have<br />

you ever heard about getting a shock from a socket, static<br />

electricity, or lightning? Those are all different types of<br />

electric charges. Those charges are also found in tiny particles of matter. The electron<br />

always has a "-", or negative, charge. The proton always has a "+", or positive, charge. If<br />

the charge of an entire atom is "0", or neutral, there are equal numbers of positive and<br />

negative pieces. Neutral means there are equal numbers of electrons and protons. The<br />

third particle is the neutron. It has a neutral charge, also known as a charge of zero. All<br />

atoms have equal numbers of protons and electrons so that they are neutral. If there are<br />

more positive protons or negative electrons in an atom, you have a special atom called<br />

an ion.


Looking at Ions<br />

We haven’t talked about ions before, so let’s get down to basics. The<br />

atomic number of an element, also called a proton number, tells you the<br />

number of protons or positive particles in an atom. A normal atom has a<br />

neutral charge with equal numbers of positive and negative particles.<br />

That means an atom with a neutral charge is one where the number of<br />

electrons is equal to the atomic number. Ions are atoms with extra<br />

electrons or missing electrons. When you are missing an electron or<br />

two, you have a positive charge. When you have an extra electron<br />

or two, you have a negative charge.<br />

What do you do if you are a sodium (Na) atom? You have eleven<br />

electrons — one too many to have an entire shell filled. You need to<br />

find another element that will take that electron away from you. When you lose that<br />

electron, you will you’ll have full shells. Whenever an atom has full shells, we say it is<br />

"happy." Let's look at chlorine (Cl). Chlorine has seventeen electrons and only needs<br />

one more to fill its third shell and be "happy." Chlorine will take your extra sodium<br />

electron and leave you with 10 electrons inside of two filled shells. You are now a happy<br />

atom too. You are also an ion and missing one electron. That missing electron gives you<br />

a positive charge. You are still the element sodium, but you are now a sodium ion (Na + ).<br />

You have one less electron than your atomic number.<br />

Ion Characteristics<br />

So now you've become a sodium ion. You have ten electrons.<br />

That's the same number of electrons as neon (Ne). But you<br />

aren't neon. Since you're missing an electron, you aren't really<br />

a complete sodium atom either. As an ion you are now<br />

something completely new. Your whole goal as an atom was<br />

to become a "happy atom" with completely filled electron<br />

shells. Now you have those filled shells. You have a lower<br />

energy. You lost an electron and you are "happy." So what<br />

makes you interesting to other atoms? Now that you have<br />

given up the electron, you are quite electrically attractive.<br />

Other electrically charged atoms (ions) of the opposite charge<br />

(negative) are now looking at you and seeing a good partner to<br />

bond with. That's where the chlorine comes in. It's not only chlorine. Almost any ion with<br />

a negative charge will be interested in bonding with you.<br />

32


Electrovalence<br />

Don't get worried about the big word. Electrovalence is just another word for something<br />

that has given up or taken electrons and become an ion. If you look at the periodic table,<br />

you might notice that elements on the left side usually become positively charged ions<br />

(cations) and elements on the right side get a negative charge (anions). That trend<br />

means that the left side has a positive valence and the right side has a negative<br />

valence. Valence is a measure of how much an atom wants to bond with other atoms. It<br />

is also a measure of how many electrons are excited about bonding with other atoms.<br />

There are two main types of bonding, covalent and electrovalent. You may have heard<br />

of the term "ionic bonds." Ionic bonds are electrovalent bonds. They are just groups of<br />

charged ions held together by electric forces. When in the presence of other ions, the<br />

electrovalent bonds are weaker because of outside electrical forces and attractions.<br />

Sodium and chlorine ions alone have a very strong bond, but as soon as you put those<br />

ions in a solution with H + (Hydrogen ion), OH - (Hydroxide), F - (Fluorine ion) or Mg ++<br />

(Magnesium ion), there are charged distractions that break the Na-Cl bond.<br />

Look at sodium chloride (NaCl) one more time. Salt is a very strong bond when it is<br />

sitting on your table. It would be nearly impossible to break those ionic/electrovalent<br />

bonds. However, if you put that salt into some water (H2O), the bonds break very<br />

quickly. It happens easily because of the electrical attraction of the water. Now you have<br />

sodium (Na + ) and chlorine (Cl - ) ions floating around the solution. You should remember<br />

that ionic bonds are normally strong, but they are very weak in water.


Neutron Madness<br />

We have already learned that ions are atoms that are<br />

either missing or have extra electrons. Let's say an atom<br />

is missing a neutron or has an extra neutron. That type of<br />

atom is called an isotope. An atom is still the same<br />

element if it is missing an electron. The same goes for<br />

isotopes. They are still the same element. They are just a<br />

little different from every other atom of the same element.<br />

For example, there are a lot of carbon (C) atoms in the<br />

Universe. The normal ones are carbon-12. Those atoms have 6 neutrons. There are a<br />

few straggler atoms that don't have 6. Those odd ones may have 7 or even 8 neutrons.<br />

As you learn more about chemistry, you will probably hear about carbon-14. Carbon-14<br />

actually has 8 neutrons (2 extra). C-14 is considered an isotope of the element carbon.<br />

Messing with the Mass<br />

If you have looked at a periodic table, you may have noticed that the atomic mass of<br />

an element is rarely an even number. That happens because of the isotopes. If you are<br />

an atom with an extra electron, it's no big deal. Electrons don't have much of a mass<br />

when compared to a neutron or proton.<br />

Atomic masses are calculated by figuring out the<br />

amounts of each type of atom and isotope there are in<br />

the Universe. For carbon, there are a lot of C-12, a<br />

couple of C-13, and a few C-14 atoms. When you<br />

average out all of the masses, you get a number that is a<br />

little bit higher than 12 (the weight of a C-12 atom). The<br />

average atomic mass for the element is actually 12.011.<br />

Since you never really know which carbon atom you are<br />

using in calculations, you should use the average mass<br />

of an atom.<br />

Bromine (Br), at atomic number 35, has a greater variety of isotopes. The atomic mass<br />

of bromine (Br) is 79.90. There are two main isotopes at 79 and 81, which average out<br />

to the 79.90amu value. The 79 has 44 neutrons and the 81 has 46 neutrons. While it<br />

won't change the average atomic mass, scientists have made bromine isotopes with<br />

masses from 68 to 97. It's all about the number of neutrons. As you move to higher<br />

atomic numbers in the periodic table, you will probably find even more isotopes for<br />

each element.<br />

34


Summary<br />

Atoms make up all matter, and are made of three parts: protons, which have a postive charge (+), neutrons, which<br />

have no charge (0), and electrons, which have a negative charge (-). Protons and neutrons make up the center of<br />

the atom, called the nucleus, and electrons float around the nucleus in orbitals. When an atom has more or less<br />

electrons than it does protons, it is called an ion. When there are less electrons that protons, it is a positive ion, and<br />

it is called a cation. When there are more electrons than protons, it is negative, and called an anion. Ions form bonds<br />

with ions of the opposite charge, and the bonds can be covalent or ionic (electrovalent). Ionic bonds are just groups of<br />

charged ions held together by elctric forces, and can be easily disruspted by outside electric forces, and especially<br />

when in water.<br />

Atoms with an extra or missing neutron are called isotopes. Neutrons and protons contribute to an atom's mass,<br />

but an electron's mass is barely noticable compared to a neutron's or proton's, so it is not included as a part of the<br />

atomic mass. The atomic amss is the average mass of an element, forming the average from all of an element's<br />

isotopes. Typically, when you go higher on the periodic table, the are more isotopes.


36


Electron Configuration<br />

Color the sublevel:<br />

s = Red<br />

d = Green<br />

p = Blue<br />

f = Orange<br />

Write in sublevels<br />

Write period, sublevel and super scripts.<br />

Ctrl Shift =<br />

gives you super scripts


The Learning Goal for this assignment is:<br />

The students will be able to describe the arrangement of electrons in atoms<br />

and predict what will happen when electrons in atoms absorb or release energy.<br />

Relate properties of atoms and their position in the periodic table to the arrangement of their electrons.<br />

www.youtube.com/watch?v=jtYzEzykFdg<br />

www.youtube.com/watch?<br />

annotation_id=annotation_2076&feature=iv&src_vid=jtYzEzykFdg&v=cOlac8ruD_0<br />

www.youtube.com/watch?<br />

annotation_id=annotation_570977&feature=iv&src_vid=cOlac8ruD_0&v=lR2vqHZWb5A<br />

Notes Section<br />

38


Electron Configuration<br />

In order to write the electron configuration for an atom you must know the 3 rules of<br />

electron configurations.<br />

1. Aufbau<br />

Notation<br />

nO e<br />

where<br />

n is the energy level<br />

O is the orbital type (s, p, d, or f)<br />

e is the number of electrons in that orbital shell<br />

Principle<br />

electrons will first occupy orbitals of the lowest energy level<br />

2. Hund rule<br />

when electrons occupy orbitals of equal energy, one electron enters each orbital until<br />

all the orbitals contain one electron with the same spin.<br />

3. Pauli exclusion principle<br />

an orbital contains a maximum of 2 electrons and<br />

paired electrons will have opposite spin


In the space below, write the unabbreviated electron configurations of the following elements:<br />

1) sodium ________________________________________________<br />

2) iron ________________________________________________<br />

3) bromine ________________________________________________<br />

4) barium ________________________________________________<br />

5) neptunium ________________________________________________<br />

In the space below, write the abbreviated electron configurations of the following elements:<br />

6) cobalt ________________________________________________<br />

4s^2 3d^7<br />

7) silver ________________________________________________<br />

[Kr] 5s^2 4d^9<br />

8) tellurium ________________________________________________<br />

[Kr] 5s^2 4d^10 5p^4<br />

9) radium ________________________________________________<br />

[Rn] 7s^2<br />

10) lawrencium ________________________________________________<br />

[Rn] 7s^2 5f^14 6d^1<br />

Determine what elements are denoted by the following electron configurations:<br />

11) 1s²s²2p⁶3s²3p⁴ ____________________<br />

sulfur [S]<br />

12) 1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s¹ ____________________<br />

Rubidium [Rb]<br />

13) [Kr] 5s²4d¹⁰5p³ ____________________<br />

Antimony [Sb]<br />

14) [Xe] 6s²4f¹⁴5d⁶ ____________________<br />

Osmium [Os]<br />

15) [Rn] 7s²5f¹¹ ____________________<br />

Einsteinium [Es]<br />

Identify the element or determine that it is not a valid electron configuration:<br />

16) 1s²2s²2p⁶3s²3p⁶4s²4d¹⁰4p⁵ ____________________<br />

Not valid (error: 4d^10)<br />

<strong>17</strong>) 1s²2s²2p⁶3s³3d⁵ ____________________<br />

Not valid (error: 3s^3)<br />

18) [Ra] 7s²5f⁸ ____________________<br />

Not valid (error: [Ra])<br />

19) [Kr] 5s²4d¹⁰5p⁵ ____________________<br />

Iodine<br />

20) [Xe] ____________________<br />

Not valid (error: [Xe])<br />

1)sodium 1s 2 2s 2 2p 6 3s 1 2)iron 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 6<br />

3)bromine 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 5 4)barium 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2<br />

5)neptunium 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 14 5d 10 6p 6 7s 2 5f 5 6)cobalt [Ar] 4s 2 3d 7<br />

7)silver [Kr] 5s 2 4d 9 8)tellurium[Kr] 5s 2 4d 10 5p 4<br />

9)radium [Rn] 7s 2 10)lawrencium[Rn] 7s 2 5f 14 6d 1<br />

1s 2 2s 2 2p 6 3s 2 3p 4 sulfur 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 1 rubidium<br />

[Kr] 5s 2 4d 10 5p 3 antimony [Xe] 6s 2 4f 14 5d 6 osmium<br />

[Rn] 7s 2 5f 11 einsteinium 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 4d 10 4p 5 not valid (take a look at “4d”)<br />

1s 2 2s 2 2p 6 3s 3 3d 5 not valid (3p comes after 3s) [Ra] 7s 2 5f 8 not valid (radium isn’t a noble gas)<br />

[Kr] 5s 2 4d 10 5p 5 valid iodine<br />

20)[Xe] not valid (an element can’t be its own electron configuration)<br />

40


Calcium [Ca]<br />

Nickel [Ni]<br />

Carbon [C]<br />

Xenon [Xe]<br />

Sulfur [S]<br />

Protactinium [Pa]<br />

You can't go on to 4p without filling 3d<br />

2s^2's electrons should flow in opposite directions<br />

1s^1<br />

1s^2 2s^2 2p^1<br />

1s^2 2s^2 2p^6 3s^1<br />

[Ar] 4s^2 3d^10 4p^6<br />

[Ar] 4s^2 3d^4<br />

1s^2 2s^2 2p^6 3s^2 3p^3<br />

1s^2 2s^2 2p^2<br />

[Ar] 4s^2 3d^6<br />

[Xe] 6s^2 4f^14 5d^10<br />

[Rn] 7s^2 5f^6<br />

1s^2 2s^2 2p^4<br />

[Ar] 4s^1


Create groups for these Scientist and explain your groupings<br />

(use the information you got from your research)<br />

Developed the Atomic Theory<br />

-Democrtius (original founder)<br />

-John Dalton (atoms make up elements, elements have different size and mass)<br />

Worked with radioactivity<br />

-Antoine Henri Becquere (discovered radioactivity)<br />

-Glenn Seaborg (discovered plutonium and 100 different isotopes)<br />

-Marie and Pierre Curie (discovered radium and polonium, and did extensive work on radioactivity)<br />

Worked on atomic particles<br />

-Eugene Goldstein (discovered protons)<br />

-J.J Thomson (discovered electrons)<br />

-James Chadwick (discovered nucleus)<br />

-Robert Milllikan (discovered electrons are negative)<br />

-Ernest Ruthford (discovered nucleus was small and dense, and that there is empty<br />

space between the nucleus and electron)<br />

Worked on the development of electron orbit<br />

-Neils Bohr (discovered electrons have specific orbits, and release quantum light when going down an energy level)<br />

-Louis de Barogilie (predicted that electrons move in waves)<br />

-Hantaro Nagaoka (established the alternative planet model for electron orbit around the nucleus)<br />

-<br />

-<br />

42


Research the Scientist and summarize their contributions to the Atomic Theory<br />

Antoine Henri Becquerel<br />

In 1896, he discovered radioactivity which contributed to the Atomic theory.<br />

He was expirementing with uranium and a photographic plate when he discovered this.<br />

Niels Bohr<br />

Based on quantum theory, he suggested that energy is transferred in specific amounts. he included that<br />

electrons have a specific orbit around the nucleus, and that a light quantum is emitted when jumping to lower<br />

energy<br />

Louis de Barogilie<br />

Known for his quantum theory research, and prediction of how electrons move in waves.<br />

Glenn Seaborg<br />

He is known mostly for his discovery of plutonium. He and his peers found 100 isotopes on the Periodic table as well.<br />

Hantaro Nagaoka<br />

Changed the model to a different planetary model, where negative electrons orbit a positive nucleus.<br />

He modeled his findings after Saturn and its rings.<br />

Democritus<br />

Came up with the Atomic Theory, Claiming that atoms were just incredibly small pieces of matter.<br />

Marie and Pierre Curie<br />

They're known for their work in radioactivity, and eventually the discovery of radium and polonium.<br />

Eugene Goldstein<br />

Helped the study of cathode rays. His expirements with them led to the discovery of protons, when cathode rays<br />

knocked off electrons and attracted them to positive molecules.<br />

Dmitri Mendeleev<br />

Published his periodic table, arranging elements by chemical properties and atomic mass. He was able to predict<br />

undiscovered elements using this table.<br />

J.J. Thomson<br />

Discovered electrons with cathide ray expirements. He showed that rays are negatively charged, and expiremented with<br />

positive particles in neon gas.<br />

James Chadwick<br />

Used alpha particles on atoms, and the radiation produced were found to be neutral particles of the same mass as<br />

protons. They came to be known as the nucleus.<br />

Erwin Shrodinger<br />

Introduced the wave mechanics model of an atom with mathematical equations, predicting where an electron could<br />

be at any time.<br />

John Dalton<br />

Proposed everything is made of atoms, atoms make elements, and all elements are different in size and mass.<br />

Lothar Meyer<br />

Pioneer in making the first periodic table, made the table with 28 elements listed by their valence shell.<br />

Robert Millikan<br />

Discovered electrons were negative during his oil expirememnts.<br />

J.W. Dobereiner<br />

Observed simliraties between elements, and predicted the development of the periodic table.<br />

Ernest Rutherford<br />

Used alpha particles on a thin layer of gold, and discovered the nucleus is small and dense, and that there is empty space<br />

between the electrons and nucleus.


The Learning Goal for this Assignment is<br />

Relate properties of atoms and their position in the periodic table to the arrangement of their electrons.<br />

Alkali Metals<br />

Very reactive, electropositive, monovalent metals forming strongly<br />

alkaline hydroxides<br />

Alkali Earth Metals<br />

Shiny, silvery-white, somewhat reactive metals at standard<br />

temperature and pressure<br />

Transitional Metals<br />

Elements with variable valence and a strong tendency to form<br />

coordination compounds, many of them being colored.<br />

Inter Transitional Metals<br />

Lanthanides and actinides<br />

(actinides are all radioactive)<br />

Metals<br />

A solid material that is typically hard, shiny, malleable, fusible, and ductile,<br />

with good electrical and thermal conductivity.<br />

Metalloids<br />

An element whose properties are of both metals and solid nonmetals,<br />

and are electrical semiconductors.<br />

Non Metals<br />

an element not having the characteristics of a metal<br />

Noble Gases<br />

Any of the elements in group 18, which are monatomic and with limited<br />

exceptions, chemically inert.<br />

44


Using Wikipedia, define the 8 categories of elements on the<br />

left page.<br />

Color your periodic table similar to the one on<br />

pages 168—169 of your book.<br />

alkali metals<br />

alkaline metals<br />

other metals<br />

transitional metals<br />

lanthanoids<br />

metalloids<br />

non metals<br />

halogens<br />

noble gases<br />

unknown elements<br />

actinoids


Atomic Size<br />

Define Atomic Size:<br />

The size of the atom is determined by how many energy levels it has<br />

and the mass of the nucleus.<br />

Increase in energy<br />

levels<br />

Increase in atomic size<br />

Explanation:<br />

46


Ionization Energy<br />

Define Ionization Energy: The energy required to remove an electron from an atom<br />

Explanation:<br />

Going down the periods on the periodic table, it gets more difficult to take away electrons from<br />

an atom because of the increase in valence shells. It gets harder to take away electrons when you go<br />

from left to right on the periodic table, because the gravitational pull of each atom increases. With the<br />

increase of mass of each element when going from left ot right on the periodic table, the pull of the<br />

electrons towards the nucleus is much stronger, so there would be a need for more energy to pull it away.


Electronegativity<br />

Define Electronegativity:<br />

Explanation:<br />

Going down the periods of the periodic table, it gets harder to add an electron, due to the number of valence<br />

shells elements have. The more valence hsells they have, the more energy the element has to put into holding<br />

an electron. Although, when going left to right through the groups of the periodic table, it gets easier to take an<br />

electron due to the increase in mass, and subsequently, the increase in gravitational pull.<br />

48


Ion Size<br />

Define Ion Size:<br />

Explanation:<br />

Ion size increases down the periods of the periodic table due to the addition of a valence shell, allowing for<br />

more space to be filled in an atom. Altough, as you go from left ot right in the groups of the periodic table, the<br />

size of the atom will actually decrease due to the increased gravitational pull, which brings the electrons in<br />

closer, so the atom is then becoming smaller.


Unit 3<br />

Chapter 25 Nuclear <strong>Chemistry</strong><br />

The students will learn what happens when an unstable<br />

nucleus decays and how nuclear chemistry affects their lives.<br />

Explore the theory of electromagnetism by comparing and contrasting the<br />

different parts of the electromagnetic spectrum in terms of wavelength,<br />

frequency, and energy, and relate them to phenomena and applications.<br />

<br />

<br />

<br />

Students will be able to compare and contrast the different parts of the<br />

electromagnetic spectrum.<br />

Students will be able to apply knowledge of the EMS to real world phenomena.<br />

Students will be able to quantitatively compare the relationship between energy,<br />

wavelength, and frequency of the EMS.<br />

amplitude<br />

wavelength<br />

frequency<br />

hertz<br />

electromagnetic radiation<br />

photon<br />

Planck’s constant<br />

Explain and compare nuclear reactions (radioactive decay, fission and<br />

fusion), the energy changes associated with them and their associated<br />

safety issues.<br />

<br />

<br />

<br />

Students will be able to compare and contrast fission and fusion reactions.<br />

Students will be able to complete nuclear decay equations to identify the type of<br />

decay.<br />

Students will participate in activities to calculate half-life.<br />

radioactivity<br />

nuclear radiation<br />

alpha particle<br />

beta particle<br />

gamma ray<br />

positron<br />

½ life<br />

transmutation<br />

fission<br />

fusion<br />

50


51<br />

Chapter 7<br />

Ionic and Metallic Bonding<br />

The students will learn how ionic compounds form and how<br />

metallic bounding affects the properties of metals.<br />

Compare the magnitude and range of the four fundamental forces<br />

(gravitational, electromagnetic, weak nuclear, strong nuclear).<br />

<br />

Students will compare/contrast the characteristics of each fundamental force.<br />

gravity<br />

electromagnetic<br />

strong<br />

weak<br />

Distinguish between bonding forces holding compounds together and other<br />

attractive forces, including hydrogen bonding and van der Waals forces.<br />

<br />

<br />

<br />

Students will be able to compare/contrast traits of ionic and covalent bonds.<br />

Students will be able to compare/contrast basic attractive forces between<br />

molecules.<br />

Students will be able to predict the type of bond or attractive force between<br />

atoms or molecules.<br />

ionic bond<br />

covalent bond<br />

metallic bond<br />

polar covalent bond<br />

hydrogen bond<br />

van der Waals forces<br />

London dispersion forces<br />

Chapter 8<br />

Covalent Bonding<br />

The students will learn how molecular bonding is different<br />

than ionic bonding and electrons affect the shape of a<br />

molecule and its properties.<br />

Interpret formula representations of molecules and compounds in terms of<br />

composition and structure.<br />

<br />

<br />

<br />

Students will be able to interpret chemical formulas in terms of # of atoms.<br />

Students will be able to differentiate between ionic and molecular compounds.<br />

Students will be able to list various VSEPR shapes and identify examples of<br />

each.<br />

Students will be able to predict shapes of various compounds.<br />

Molecule<br />

empirical formula<br />

<br />

Atom<br />

Electron<br />

Element<br />

Compound


Leonardo Gutierrez<br />

Name ____________________<br />

Go to the web site www.darvill.clara.net/emag<br />

1. Click on “How the waves fit into the spectrum” and fill in this table:<br />

>: look out for the<br />

RED words on the web site!<br />

frequency<br />

Low __________, Long wavelength<br />

wavelength<br />

High frequency, Short ______________<br />

Radio Waves<br />

micro waves infrared waves visible light ultravioet waves X-ray waves<br />

Gamma rays<br />

2. Click on “Radio waves”. They are used for _______________________<br />

communication<br />

3. Click on “Microwaves”. They are used for cooking, mobile _________, transmitters _______ speed cameras and _________.<br />

radar<br />

4. Click on “Infra-red”. These waves are given off by _____ hot _________. objects They are used for remote controls,<br />

cameras in police ____________ helicopters , and alarm systems.<br />

5. Click on “Visible Light”. This is used in ___ DVD players and _______ laser printers, and for seeing where we’re going.<br />

6. “UV” stands for “ ________ ultra ___________”. violet This can damage the _________ retina in your eyes, and cause<br />

sunburn and even _______ skin cancer. Its uses include detecting forged ______ bank _______. notes<br />

7. X-rays are used to see inside people, and for _________ airport security.<br />

8. Gamma rays are given off by some ________________ substances. We can use them to kill ________ cells,<br />

which is called R_______________ adiotherapy .<br />

9. My Quiz score is ____%. 100<br />

radioactive<br />

cancer<br />

52


53<br />

10. Name ________________________________<br />

Go to the web site www.darvill.clara.net/emag<br />

Name How they’re made Uses Dangers<br />

Gamma rays<br />

X-Rays<br />

UV Waves<br />

Visible light<br />

Infrared waves<br />

Micro waves<br />

Radio waves<br />

given off by stars and some<br />

radioactive substances<br />

given off by stars, and strongly<br />

by some types of nebula<br />

Special lamps (sun beds)<br />

given off by the sun in huge<br />

doses<br />

given off by anything that's hot<br />

enough to glow<br />

given off by hot objects: stars,<br />

lamps, flames, humans<br />

emitted by various transmitters<br />

stars also give off MW<br />

transmitters, stars, sparks,<br />

lightning<br />

radiotherapy, tracers (for<br />

scanning and making pictures<br />

of a patient)<br />

X-rays, airport scanners, space<br />

telescopes<br />

Sun tan, detecting forged bank<br />

notes, blacklights, killing<br />

microbes and sterilization<br />

Seeing things, DVD, laser<br />

printers, weapon aiming<br />

systems<br />

remote controls, healing sport<br />

injuries, night sights, alarm<br />

systems<br />

cooking, wi-fi, speed cameras,<br />

radar, smart phones (phones<br />

in general)<br />

Communications: AM, FM,<br />

UHF police radio, TV<br />

cell damage<br />

variety of cancers<br />

mutations in tissue<br />

cell damage<br />

cancers<br />

large doses damage<br />

retina, cause sunburn<br />

and skin cancer<br />

to much damages<br />

the retina<br />

overheating<br />

significant levels can<br />

give cataracts<br />

large doses: cancer,<br />

leukemia<br />

_____ Frequency _____ frequency,<br />

Short wavelength ______ Wavelength


Learning Goal for this section:<br />

The students will learn what happens when an unstable nucleus decays and how nuclear chemistry affects their lives.<br />

Notes Section:<br />

Neutrons are neutral because they are both positive and negative (+,-)=0<br />

Isotopes are variant atoms with more/less neutrons, with different masses<br />

If an atom is equal in protons and neutrons, it is stable. Isotopes that are radioactive are unstable, as they're releasing<br />

neutrons.<br />

There is a certain amount of carbon when something is processed or created, and knowing the half-life, you can use that<br />

half-life to determine the age of something (carbon dating).<br />

Everything organic has a certain amount of carbon in it, making it possible to carbon date most previously living things.<br />

Helium (He) is the only alpha particle, and any radioactive decay leads to new products<br />

There is only one Helium per alpha radiation, and it results in two different products.<br />

Uranium 238(mass #) has 92 protons, and when it goes through alpha radiation, it would give out a Helium, which would give<br />

off two protons (#of Protons per Helium) and two neutrons, (the atomic mass of helium is 4, two neutrons & 2 protons) giving<br />

this equation: Ur238(92P)->*alpha radiation*->Thorium234(90P)+He4(2P)<br />

Alpha particle radiation on an element makes the element on the periodic table go down by 2 (Uranium down by 2=Thorium)<br />

Beta particles are electrons, and beta radiation is neutron (+,- =0) losing the negative charge inside, turning it into (+), becom<br />

proton. ex: C14(6P,8N)->*beta radiation*->N14(7P7N)<br />

Negative Beta radiation leads to an element going up by 1 in th eperiodic table. ex: C14(6P8N)->*beta raditation*->N14(7PN<br />

Positive Beta radiation takes a proton giving up a positive electron charge (e+), turning it into a neutron<br />

ex: B8 (Boron P5 N3)->*positive beta radiation*->Be (Berylium P4 N4) +e(+)<br />

Gamma Energy: Gamma radiation is just energy being released, associated with Alpha or Beta radiation (is like a byproduct)<br />

Half-life: given a radiaoctive substance, half life is the period of time it will take to lose half the mass it started with.<br />

2 types of reactions: fission and fusion<br />

Fusion- Combining atoms into a larger atom<br />

Fission- Splitting of an atom (ex: shooting a neutron into Uranium 235,<br />

54


The Nucleus<br />

A typical model of the atom is called the Bohr Model, in<br />

honor of Niels Bohr who proposed the structure in 1913. The Bohr atom consists of a central nucleus<br />

composed of neutrons and protons, which is surrounded by electrons which “orbit” around the nucleus.<br />

Protons carry a positive charge of one and have a mass of about 1 atomic mass unit or amu (1 amu =1.7x10-<br />

27 kg, a very, very small number). Neutrons are electrically “neutral” and also have a mass of about 1 amu. In<br />

contrast electron carry a negative charge and have mass of only 0.00055 amu. The number of protons in a<br />

nucleus determines the element of the atom. For example, the number of protons in uranium is 92 and the<br />

number in neon is 10. The proton number is often referred to as Z.<br />

Atoms with different numbers of protons are called elements, and are arranged in the periodic table with<br />

increasing Z.<br />

Atoms in nature are electrically neutral so the number of electrons orbiting the nucleus equals the number of<br />

protons in the nucleus.<br />

Neutrons make up the remaining mass of the nucleus and provide a means to “glue” the protons in place.<br />

Without neutrons, the nucleus would split apart because the positive protons would repel each other. Elements<br />

can have nucleii with different numbers of neutrons in them. For example hydrogen, which normally only has<br />

one proton in the nucleus, can have a neutron added to its nucleus to from deuterium, ir have two neutrons<br />

added to create tritium, which is radioactive. Atoms of the same element which vary in neutron number are<br />

called isotopes. Some elements have many stable isotopes (tin has 10) while others have only one or two. We<br />

express isotopes with the nomenclature Neon-20 or 20 Ne 10, with twenty representing the total number of<br />

neutrons and protons in the atom, often referred to as A, and 10 representing the number of protons (Z).<br />

Alpha Particle<br />

Decay<br />

Alpha decay is a radioactive process in which a<br />

particle with two neutrons and two protons is<br />

ejected from the nucleus of a radioactive atom. The particle is identical to the nucleus of a helium atom.<br />

Alpha decay only occurs in very heavy elements such as uranium, thorium and radium. The nuclei of these<br />

atoms are very “neutron rich” (i.e. have a lot more neutrons in their nucleus than they do protons) which makes<br />

emission of the alpha particle possible.<br />

After an atom ejects an alpha particle, a new parent atom is formed which has two less neutrons and two less<br />

protons. Thus, when uranium-238 (which has a Z of 92) decays by alpha emission, thorium-234 is created<br />

(which has a Z of 90).<br />

Because alpha particles contain two protons, they have a positive charge of two. Further, alpha particles are<br />

very heavy and very energetic compared to other common types of radiation. These characteristics allow alpha<br />

particles to interact readily with materials they encounter, including air, causing many ionizations in a very short<br />

distance. Typical alpha particles will travel no more than a few centimeters in air and are stopped by a sheet of<br />

paper.


Beta Particle Decay<br />

Beta decay is a radioactive process in which an electron is emitted from the nucleus of a radioactive<br />

atom Because this electron is from the nucleus of the atom, it is called a beta particle to distinguish it<br />

from the electrons which orbit the atom.<br />

Like alpha decay, beta decay occurs in isotopes which are “neutron rich” (i.e. have a lot more<br />

neutrons in their nucleus than they do protons). Atoms which undergo beta decay are located below<br />

the line of stable elements on the chart of the nuclides, and are typically produced in nuclear reactors.<br />

When a nucleus ejects a beta particle, one of the neutrons in the nucleus is transformed into a proton.<br />

Since the number of protons in the nucleus has changed, a new daughter atom is formed which has<br />

one less neutron but one more proton than the parent. For example, when rhenium-187 decays<br />

(which has a Z of 75) by beta decay, osmium-187 is created (which has a Z of 76). Beta particles<br />

have a single negative charge and weigh only a small fraction of a neutron or proton. As a result, beta<br />

particles interact less readily with material than alpha particles. Depending on the beta particles<br />

energy (which depends on the radioactive atom), beta particles will travel up to several meters in air,<br />

and are stopped by thin layers of metal or plastic.<br />

Positron emission or beta plus decay (β+ decay) is a subtype of radioactive decay called beta decay,<br />

in which a proton inside a radionuclide nucleus is converted into a neutron while releasing a positron<br />

and an electron neutrino (νe). Positron emission is mediated by the weak force.<br />

An example of positron emission (β+ decay) is shown with magnesium-23 decaying into sodium-23:<br />

23 Mg12 → 23 Na11 + e +<br />

Because positron emission decreases proton number relative to neutron number, positron decay<br />

happens typically in large "proton-rich" radionuclides. Positron decay results in nuclear transmutation,<br />

changing an atom of one chemical element into an atom of an element with an atomic number that is<br />

less by one unit.<br />

Positron emission should not be confused with electron emission or beta minus decay (β− decay),<br />

which occurs when a neutron turns into a proton and the nucleus emits an electron and an<br />

antineutrino.<br />

56


57<br />

Gamma<br />

Radiation<br />

After a decay reaction, the nucleus is often in an<br />

“excited” state. This means that the decay has<br />

resulted in producing a nucleus which still has<br />

excess energy to get rid of. Rather than emitting another beta or alpha particle, this energy is lost by<br />

emitting a pulse of electromagnetic radiation called a gamma ray. The gamma ray is identical in<br />

nature to light or microwaves, but of very high energy.<br />

Like all forms of electromagnetic radiation, the gamma ray has no mass and no charge. Gamma rays<br />

interact with material by colliding with the electrons in the shells of atoms. They lose their energy<br />

slowly in material, being able to travel significant distances before stopping. Depending on their initial<br />

energy, gamma rays can travel from 1 to hundreds of meters in air and can easily go right through<br />

people.<br />

It is important to note that most alpha and beta emitters also emit gamma rays as part of their decay<br />

process. However, their is no such thing as a “pure” gamma emitter. Important gamma emitters<br />

including technetium-99m which is used in nuclear medicine, and cesium-137 which is used for<br />

calibration of nuclear instruments.<br />

Half Life<br />

Half-life is the time required for the quantity of a<br />

radioactive material to be reduced to one-half its<br />

original value.<br />

All radionuclides have a particular half-life, some<br />

of which a very long, while other are extremely<br />

short. For example, uranium-238 has such a<br />

long half life, 4.5x109 years, that only a small fraction has decayed since the earth was formed. In<br />

contrast, carbon-11 has a half-life of only 20 minutes. Since this nuclide has medical applications, it<br />

has to be created where it is being used so that enough will be present to conduct medical studies.


The Learning Goal for this assignment is:<br />

Distinguish between bonding forces holding compounds together and other attractive forces, including hydrogen<br />

bonding and van der Waals forces.<br />

Introduction to Ionic Compounds<br />

Those molecules that consist of charged ions with opposite charges are called IONIC. These ionic<br />

compounds are generally solids with high melting points and conduct electrical current. Ionic<br />

compounds are generally formed from metal and a non-metal elements. See Ionic Bonding below.<br />

Ionic Compound Example<br />

For example, you are familiar with the fairly benign unspectacular behavior of common white<br />

crystalline table salt (NaCl). Salt consists of positive sodium ions (Na + ) & negative chloride ions (Cl - ).<br />

On the other hand the element sodium is a silvery gray metal composed of neutral atoms which react<br />

vigorously with water or air. Chlorine as an element is a neutral greenish-yellow, poisonous, diatomic<br />

gas (Cl2).<br />

The main principle to remember is that ions are completely different in physical and chemical<br />

properties from the neutral atoms of the elements.<br />

The notation of the + and - charges on ions is very important as it conveys a definite meaning.<br />

Whereas elements are neutral in charge, IONS have either a positive or negative charge depending<br />

upon whether there is an excess of protons (positive ion) or excess of electrons (negative ion).<br />

Formation of Positive Ions<br />

Metals usually have 1-4 electrons in the outer energy level. The electron arrangement of a rare gas is<br />

most easily achieved by losing the few electrons in the newly started energy level. The number of<br />

electrons lost must bring the electron number "down to" that of a prior rare gas.<br />

How will sodium complete its octet?<br />

First examine the electron arrangement of the atom. The atomic number is eleven, therefore, there<br />

are eleven electrons and eleven protons on the neutral sodium atom. Here is the Bohr diagram and<br />

Lewis symbol for sodium:<br />

58


This analysis shows that sodium has only one electron in its outer level. The nearest rare gas is neon<br />

with 8 electron in the outer energy level. Therefore, this electron is lost so that there are now eight<br />

electrons in the outer energy level, and the Bohr diagrams and Lewis symbols for sodium ion and<br />

neon are identical. The octet rule is satisfied.<br />

Ion Charge?<br />

What is the charge on sodium ion as a result of losing one electron? A comparison of the atom and<br />

the ion will yield this answer.<br />

Sodium Atom<br />

Sodium Ion<br />

11 p+ to revert to 11 p + Protons are identical in<br />

12 n an octet 12 n<br />

the atom and ion.<br />

Positive charge is<br />

11 e- lose 1 electron 10 e-<br />

caused by lack of<br />

0 charge + 1 charge<br />

electrons.<br />

Formation of Negative Ions<br />

How will fluorine complete its octet?<br />

First examine the electron arrangement of the atom. The atomic number is nine, therefore, there are<br />

nine electrons and nine protons on the neutral fluorine atom. Here is the Bohr diagram and Lewis<br />

symbol for fluorine:<br />

This analysis shows that fluorine already has seven electrons in its outer level. The nearest rare gas<br />

is neon with 8 electron in the outer energy level. Therefore only one additional electron is needed to<br />

complete the octet in the fluorine atom to make the fluoride ion. If the one electron is added, the Bohr<br />

diagrams and Lewis symbols for fluorine and neon are identical. The octet rule is satisfied.<br />

59


Ion Charge?<br />

What is the charge on fluorine as a result of adding one electron? A comparison of the atom and the<br />

ion will yield this answer.<br />

Fluorine Atom Fluoride Ion *<br />

9 p+ to complete 9 p + Protons are identical in<br />

10 n octet 10 n<br />

9 e- add 1 electron 10 e-<br />

0 charge - 1 charge<br />

the atom and ion.<br />

Negative charge is<br />

caused by excess<br />

electrons<br />

* The "ide" ending in the name signifies a simple negative ion.<br />

Summary Principle of Ionic Compounds<br />

An ionic compound is formed by the complete transfer of electrons from a metal to a nonmetal and<br />

the resulting ions have achieved an octet. The protons do not change. Metal atoms in Groups 1-3<br />

lose electrons to non-metal atoms with 5-7 electrons missing in the outer level. Non-metals gain 1-4<br />

electrons to complete an octet.<br />

Octet Rule<br />

Elemental atoms generally lose, gain, or share electrons with other atoms in order to achieve the<br />

same electron structure as the nearest rare gas with eight electrons in the outer level.<br />

The proper application of the Octet Rule provides valuable assistance in predicting and explaining<br />

various aspects of chemical formulas.<br />

Introduction to Ionic Bonding<br />

Ionic bonding is best treated using a simple<br />

electrostatic model. The electrostatic model<br />

is simply an application of the charge<br />

principles that opposite charges attract and<br />

similar charges repel. An ionic compound<br />

results from the interaction of a positive and<br />

negative ion, such as sodium and chloride in<br />

common salt.<br />

The IONIC BOND results as a balance<br />

between the force of attraction between<br />

opposite plus and minus charges of the ions<br />

and the force of repulsion between similar<br />

negative charges in the electron clouds. In<br />

crystalline compounds this net balance of<br />

forces is called the LATTICE ENERGY.<br />

Lattice energy is the energy released in the<br />

formation of an ionic compound.<br />

DEFINITION: The formation of an IONIC<br />

BOND is the result of the transfer of one or<br />

more electrons from a metal onto a nonmetal.<br />

60


61<br />

Metals, with only a few electrons in the outer energy level, tend to lose electrons most readily. The<br />

energy required to remove an electron from a neutral atom is called the IONIZATION POTENTIAL.<br />

Energy + Metal Atom ---> Metal (+) ion + e-<br />

Non-metals, which lack only one or two electrons in the outer energy level have little tendency to lose<br />

electrons - the ionization potential would be very high. Instead non-metals have a tendency to gain<br />

electrons. The ELECTRON AFFINITY is the energy given off by an atom when it gains electrons.<br />

Non-metal Atom + e- --- Non-metal (-) ion + energy<br />

The energy required to produce positive ions (ionization potential) is roughly balanced by the energy<br />

given off to produce negative ions (electron affinity). The energy released by the net force of<br />

attraction by the ions provides the overall stabilizing energy of the compound.<br />

Notes Section:<br />

Ionic Compounds Example:<br />

Ions are completely different in physcial and chemical properties from their neutral atom of the element<br />

Ions are positive(+) or negative(-) based on excess of protons(+) or electrons (-)<br />

Formation of Positive Ions:<br />

It's easier for rare gases to get rid of their ve- to go down to prior energy levels to be stable<br />

ex: Na* -> (to form ion, lose electron) -> Na(+1)<br />

Ion Charge:<br />

Protons stay the same in the atom or ion, only electrons change<br />

Summary Principle of Ionic Copmounds:<br />

Ioninc compounds are formed by the complete transfer of electrons from a metal to non-metal, resulting<br />

in octet ions.<br />

Metals in groups 1,2, and 13 lose electrons to non-metals in groups 15-<strong>17</strong> that need 1-3 electrons<br />

Octet Rule:<br />

Elemental atoms lose/gain/share atoms to achieve the electron structure of the prior noble gas<br />

The Octet Rule assists in predicting and explaining various chemical formulas<br />

Intro to Ionic Bonding:<br />

Ionic compounds result from positive(+) and negative(-) ions<br />

Ionic bonds result from attraction between opposite charges and repulsion from like charges.<br />

In crystalline compounds, the net balance is called Lattice Energy, which is the energy released in the formation<br />

of an ionic compound<br />

Ionic Bond- the result of the transfer of 1 or more electrons from a metal to a non-metal<br />

Ionization Potential- energy required to remove na electron from a neutral atom<br />

Electron Affinity- energy given off by an atom when it gains electrons<br />

Energy released by the net force of attraction by ions provides overall stabilizing energy of the compound<br />

(Ionization potential is balaced by Electron Affinity)


The Learning Goal for this assignment is:<br />

Distinguish between bonding forces holding compounds together and other attractive forces, including<br />

hydrogen bonding and Van Der Waals forces.<br />

Introduction to Covalent Bonding:<br />

Bonding between non-metals consists of two electrons shared between two atoms. Using the Wave<br />

Theory, the covalent bond involves an overlap of the electron clouds from each atom. The electrons<br />

are concentrated in the region between the two atoms. In covalent bonding, the two electrons shared<br />

by the atoms are attracted to the nucleus of both atoms. Neither atom completely loses or gains<br />

electrons as in ionic bonding.<br />

There are two types of covalent bonding:<br />

1. Non-polar bonding with an equal sharing of electrons.<br />

2. Polar bonding with an unequal sharing of electrons. The number of shared electrons depends on<br />

the number of electrons needed to complete the octet.<br />

NON-POLAR BONDING results when two identical non-metals equally share electrons between<br />

them. One well known exception to the identical atom rule is the combination of carbon and hydrogen<br />

in all organic compounds.<br />

Hydrogen<br />

The simplest non-polar covalent molecule is hydrogen. Each hydrogen<br />

atom has one electron and needs two to complete its first energy level.<br />

Since both hydrogen atoms are identical, neither atom will be able to<br />

dominate in the control of the electrons. The electrons are therefore<br />

shared equally. The hydrogen covalent bond can be represented in a<br />

variety of ways as shown here:<br />

The "octet" for hydrogen is only 2 electrons since the nearest rare gas is<br />

He. The diatomic molecule is formed because individual hydrogen atoms<br />

containing only a single electron are unstable. Since both atoms are<br />

identical a complete transfer of electrons as in ionic bonding is<br />

impossible.<br />

Instead the two hydrogen atoms SHARE both electrons equally.<br />

Oxygen<br />

Molecules of oxygen, present in about 20% concentration in air are<br />

also covalent molecules. See the graphic on the left of the Lewis Dot<br />

Structure.<br />

There are 6 electrons in the outer shell, therefore, 2 electrons are<br />

needed to complete the octet. The two oxygen atoms share a total of<br />

four electrons in two separate bonds, called double bonds.<br />

The two oxygen atoms equally share the four electrons.<br />

62


POLAR BONDING results when two different non-metals unequally share electrons between them.<br />

One well known exception to the identical atom rule is the combination of carbon and hydrogen in all<br />

organic compounds.<br />

The non-metal closer to fluorine in the Periodic Table has a greater tendency to keep its own electron<br />

and also draw away the other atom's electron. It is NOT completely successful. As a result, only<br />

partial charges are established. One atom becomes partially positive since it has lost control of its<br />

electron some of the time. The other atom becomes partially negative since it gains electron some of<br />

the time.<br />

Hydrogen Chloride<br />

Hydrogen Chloride forms a polar covalent molecule. The graphic<br />

on the left shows that chlorine has 7 electrons in the outer shell.<br />

Hydrogen has one electron in its outer energy shell. Since 8<br />

electrons are needed for an octet, they share the electrons.<br />

However, chlorine gets an unequal share of the two electrons,<br />

although the electrons are still shared (not transferred as in ionic<br />

bonding), the sharing is unequal. The electrons spends more of the<br />

time closer to chlorine. As a result, the chlorine acquires a "partial"<br />

negative charge. At the same time, since hydrogen loses the<br />

electron most - but not all of the time, it acquires a "partial" charge.<br />

The partial charge is denoted with a small Greek symbol for delta.<br />

Water<br />

Water, the most universal compound on all of the earth, has the property of<br />

being a polar molecule. As a result of this property, the physical and<br />

chemical properties of the compound are fairly unique.<br />

Dihydrogen Oxide or water forms a polar covalent molecule. The graphic on<br />

the left shows that oxygen has 6 electrons in the outer shell. Hydrogen has<br />

one electron in its outer energy shell. Since 8 electrons are needed for an<br />

octet, they share the electrons.<br />

Notes Section:<br />

Formula charges 3 steps:<br />

1- Count Valence electrons<br />

2- Find central atom, Subtract electrons in bonds from the total, Add Lone pairs to the compound,<br />

Add LP & Double/Triple Bonds (Steps 2-8)<br />

3- Find formal charges. Get the charges as close to zero as possible by moving electrons and bonds<br />

A central atom in period two can be an exception to the octic rule<br />

Covalent bonding- non-metals with a bond of 2 electrons being shared between 2 atoms, neither atom fully gaining/losing a<br />

2 types of covalent bonding: Polar and Non-polar<br />

Non-polar: Two atoms of the same non-metal equally sharing electrons.<br />

Polar: Two different non-metals unequally sharing electrons, with the more electronegative being partially negative, the less<br />

partially positive.<br />

63


C 2 H 6 O Ethanol CH 3 CH 2 O<br />

Step 1<br />

Find valence e- for all atoms. Add them together.<br />

C: 4 x 2 = 8<br />

H: 1 x 6 = 6<br />

O: 6<br />

Total = 20<br />

Step 2<br />

Find octet e- for each atom and add them together.<br />

C: 8 x 2 = 16<br />

H: 2 x 6 = 12<br />

O: 8<br />

Total = 36<br />

Step 3<br />

Subtract Step 1 total from Step 2.<br />

Gives you bonding e-.<br />

36 – 20 = 16e-<br />

Step 4<br />

Find number of bonds by diving the number in step 3 by 2<br />

(because each bond is made of 2 e-)<br />

16e- / 2 = 8 bond pairs<br />

These can be single, double or triple bonds.<br />

Step 5<br />

Determine which is the central atom<br />

Find the one that is the least electronegative.<br />

Use the periodic table and find the one farthest<br />

away from Fluorine or<br />

The one that only has 1 atom.<br />

64


Step 6<br />

Put the atoms in the structure that you think it will<br />

have and bond them together.<br />

Put Single bonds between atoms.<br />

Step 7<br />

Find the number of nonbonding (lone pairs) e-.<br />

Subtract step 3 number from step 1.<br />

20 – 16 = 4e- = 2 lone pairs<br />

Step 8<br />

Complete the Octet Rule by adding the lone<br />

pairs.<br />

Add any left over bonds to make double or triple<br />

bonds.<br />

Then, if needed, use any lone pairs to make<br />

double or triple bonds so that all atoms meet<br />

the Octet Rule.<br />

See Step 4 for total number of bonds.<br />

Step 9<br />

Find the formal charges for the atoms in the compound.<br />

Arrange atoms so that all formal charges<br />

are as close to 0 as possible.<br />

Some central atoms do not meet the octet rule.<br />

Boron can sometimes have only 6 electrons and<br />

some elements in Periods 3—7 may exceed the<br />

octet rule.


Linear<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

sp AX 2 None 180<br />

BeCl 2<br />

Beryllium Dichloride<br />

Cl<br />

Be<br />

Cl<br />

element bond lone pair<br />

C<br />

66


Trigonal Planar<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

Sp 2 AX 3 None 120<br />

BF 3<br />

F<br />

F<br />

B<br />

F<br />

Boron Trifluoride<br />

element bond lone pair


Bent<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

Sp2 AX 2 E 1 114<br />

O 3<br />

Tri Oxide<br />

O<br />

O<br />

O<br />

element bond lone pair<br />

68


Tetrahedral<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

Sp 3 AX 4 0 109.5<br />

PO 4<br />

3-<br />

O<br />

-3<br />

Phosphate<br />

O<br />

P<br />

O<br />

O<br />

element bond lone pair<br />

C


Trigonal Pyramidal<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

sp 3 AX 3 E 1 107<br />

PH 3<br />

Phosphorous Trihydride<br />

H<br />

H<br />

P<br />

H<br />

element bond lone pair<br />

C<br />

70


71<br />

Bent<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

Sp 3 AX 2 E 2 2 104.5<br />

H 2 O<br />

Dihydrogen Oxide<br />

H<br />

O H<br />

element bond lone pair<br />

C


Trigonal Bi Pyramidal<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

sp 3 d AX 5 0 120/90<br />

PCl 5<br />

Phosphorous Pentachloride<br />

Cl<br />

Cl<br />

Cl<br />

P<br />

Cl<br />

Cl<br />

element bond lone pair<br />

C<br />

72


73<br />

T-Shaped<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

Sp 3 d AX 3 E 2 2 90<br />

ClF 3<br />

Chlorine Trifluoride<br />

F<br />

Cl F<br />

F<br />

element bond lone pair<br />

C


Octahedral<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

Sp 3 d 2 AX 6 0 90<br />

SF 6<br />

F<br />

F<br />

F<br />

S<br />

F<br />

F<br />

F<br />

Sulfur Hexafluoride<br />

element bond lone pair<br />

C<br />

74


75<br />

Square Planar<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

Sp 3 d 2 AX 4 E 2 2 90<br />

ICl 4<br />

-<br />

Iodine Tetrachloride Ion<br />

C<br />

-4<br />

C I C<br />

C<br />

element bond lone pair<br />

C


Orbitals Equation Lone Pairs<br />

Angle<br />

sp AX2 None 180<br />

sp 2 AX3 None 120<br />

Sp2 AX2E 1 114<br />

sp3 AX4 None 109.5<br />

Linear<br />

Name<br />

Trigonal Planal<br />

Bent<br />

Tetrahedral<br />

Sp3 AX3E 1 107<br />

Trigonal Pyramidal<br />

Sp3 AX2E2 2 104.5<br />

Bent<br />

Sp3d AX5 none 120/90 Trigonal Bi Pyramidal<br />

Sp3d AX3E2 2 90<br />

T-Shaped<br />

Sp3d2 AX6 None 90<br />

Octahedral<br />

Sp3d2 AX4E2 2 90<br />

Square Planar<br />

76


Name Formula Charge<br />

Dichromate Cr₂O₇ 2-<br />

Sulfate SO₄ 2-<br />

Hydrogen Carbonate HCO₃ 1-<br />

Hypochlorite ClO 1-<br />

Phosphate PO₄ 3-<br />

Nitrite NO₂ 1-<br />

Chlorite ClO₂ 1-<br />

Dihydrogen phosphate H₂PO₄ 1-<br />

Chromate CrO₄ 2-<br />

Carbonate CO₃ 2-<br />

Hydroxide OH 1-<br />

Hydrogen phosphate HPO₄ 2-<br />

Ammonium NH₄ 1+<br />

Acetate C₂H₃O₂ 1-<br />

Perchlorate ClO₄ 1-<br />

Permanganate MnO₄ 1-<br />

Chlorate ClO₃ 1-<br />

Hydrogen Sulfate HSO₄ 1-<br />

Phosphite PO₃ 3-<br />

Sulfite SO₃ 2-<br />

Silicate SiO₃ 2-<br />

Nitrate NO₃ 1-<br />

Hydrogen Sulfite HSO₃ 1-<br />

Oxalate C₂O₄ 2-<br />

Cyanide CN 1-<br />

Hydronium H₃O 1+<br />

Thiosulfate S₂O₃ 2-


Chapter 9<br />

Unit 4<br />

Chemical Names and Formulas<br />

The students will learn how the periodic table helps them<br />

determine the names and formulas of ions and compounds.<br />

Chapter 22 Hydrocarbon Compounds<br />

The student will learn how Hydrocarbons are named and the<br />

general properties of Hydrocarbons.<br />

Describe how different natural resources are produced and how their rates<br />

of use and renewal limit availability.<br />

<br />

<br />

<br />

Students will explore local, national, and global renewable and nonrenewable<br />

resources.<br />

Students will explain the environmental costs of the use of renewable and<br />

nonrenewable resources.<br />

Students will explain the benefits of renewable and nonrenewable resources.<br />

Nuclear reactors<br />

Natural gas<br />

Petroleum<br />

Refining<br />

Coal<br />

78


Chapter 23 Functional Groups<br />

The student will learn what effects functional groups have on<br />

organic compounds and how chemical reactions are used in<br />

organic compounds.<br />

Describe the properties of the carbon atom that make the diversity of carbon<br />

compounds possible.<br />

Identify selected functional groups and relate how they contribute to<br />

properties of carbon compounds.<br />

<br />

<br />

Students will identify examples of important carbon based molecules.<br />

Students will create 2D or 3D models of carbon molecules and explain why this<br />

molecule is important to life.<br />

covalent bond<br />

single bond<br />

double bond<br />

triple bond<br />

monomer<br />

polymer<br />

79


80<br />

Learning Goal: Describe the properties of the carbon atom that make the diversity of carbon compounds possible. Identify<br />

selected functional groups and relate how they contribute to properties of carbon compounds.<br />

http://www.bbc.co.uk/education/guides/zm9hvcw/revision<br />

Notes:<br />

Prefix for # of carbon atoms:<br />

(M) monsters (meth-)<br />

(E) eat (eth-)<br />

(P) pupils (prop-)<br />

(B) but (but-)<br />

(P) prefer (pent-)<br />

(H) hairy (hex-)<br />

(H) haggis (hept-)<br />

(O) occasionally (oct-)<br />

(N) not (non-)<br />

(D) distinctly (Deci-)


81


Unit 5<br />

Chapter 10 Chemical Quantities<br />

The student will learn why the mole is important and how the<br />

molecular formula of a compound can be determined<br />

experimentally.<br />

Chapter 11 Chemical Reactions<br />

The students will learn how chemical reactions obey the law of<br />

conservation of mass and how they can predict the products<br />

of a chemical reaction.<br />

Characterize types of chemical reactions, for example: redox, acid-base,<br />

synthesis, and single and double replacement reactions.<br />

<br />

<br />

<br />

<br />

Students will be able to identify the type of chemical reaction that occurs.<br />

Students will be able to compare/contrast reactants and products of various<br />

types of chemical reactions.<br />

Students will be able to predict the product of various reactants.<br />

Students will be able to write balanced chemical equations for each type of<br />

reaction.<br />

Decomposition<br />

Combustion<br />

Redox<br />

Acid-Base<br />

Synthesis<br />

single-replacement<br />

double-replacement<br />

Differentiate between chemical and nuclear reactions.<br />

Students will compare/contrast chemical and nuclear reactions.<br />

fission<br />

fusion<br />

82


Chapter 12 Stoichiometry<br />

The students will learn how balanced chemical equations are<br />

used in stoichiometric calculations and how to calculate<br />

amounts of reactants and products in a chemical equation.<br />

Apply the mole concept and the law of conservation of mass to calculate<br />

quantities of chemicals participating in reactions.<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

Students will be able to use a balanced equation to determine mole ratios.<br />

Students will be able to apply law of conservation of mass to chemical equations.<br />

Students will be able to calculate empirical and molecular formulas.<br />

Students will be able to calculate the % composition of a compound.<br />

Students will be able to calculate theoretical yield.<br />

Students will be able to calculate % error.<br />

Students will be able to calculate molar mass.<br />

Students will be able to perform stoichiometric calculations, including limiting<br />

reagents.<br />

mole<br />

Avogadro’ s number<br />

molar mass<br />

gram formula mass<br />

83


www.youtube.com/watch?v=AsqEkF7hcII<br />

www.youtube.com/watch?v=tEn0N4R2dqA<br />

www.youtube.com/watch?v=Pft2CASl0M0<br />

www.youtube.com/watch?v=rwhJklbK8R0<br />

The Mole<br />

(Bozeman Science Vid):<br />

1 mole is equivlaent to avogadro's number worth of atoms/molecules of a substance.<br />

ex: 1 mole of Hydrogen (H) = 6.02x10^23 atoms of Hydrogen (H)<br />

ex: 1 mole of Water (H^2O) = 6.02*10^23 molecules of water (H^2O)<br />

*The mole is the bridge between number of atoms and actual mass of a substance*<br />

1 mole is the amount of atoms in a molecule equivalent to Avogadro's # (determined by the molar mass of the subs<br />

Mole:Mole Ratio-<br />

A ratio of the amount of reactants and products using the coefficients of a chemical reaction (balanced equation)<br />

ex: 1Cu + 2AgNO^3 -> 2Ag + 1Cu(NO^3)^2<br />

^<br />

coefficient<br />

^ ^coefficient<br />

^<br />

*Mole ratios are used as a conversion factor to change between substances in a chemical reaction*<br />

Mole of Substance A -> Mole of Substance B<br />

84


www.youtube.com/watch?v=BTRm8PwcZ3U<br />

www.youtube.com/watch?v=F9NkYSKJifs<br />

www.youtube.com/watch?v=xPdqEX_WMjo<br />

Molar Mass<br />

85


86<br />

Categories of Reactions<br />

All chemical reactions can be placed into one of six categories. Here they are, in no<br />

particular order:<br />

1) Synthesis: A synthesis reaction is when two or more simple compounds combine to form a<br />

more complicated one. These reactions come in the general form of:<br />

One example of a synthesis reaction is the combination of iron and sulfur to form iron (II) sulfide:<br />

8 Fe + S8 ---> 8 FeS<br />

If two elements or very simple molecules combine with each other, it’s probably a synthesis reaction.<br />

The products will probably be predictable using the octet rule to find charges.<br />

2) Decomposition: A decomposition reaction is the opposite of a synthesis reaction - a<br />

complex molecule breaks down to make simpler ones. These reactions come in the general form:<br />

One example of a decomposition reaction is the electrolysis of water to make oxygen and hydrogen<br />

gas:<br />

2 H2O ---> 2 H2 + O2<br />

If one compound has an arrow coming off of it, it’s probably a decomposition reaction. The products<br />

will either be a couple of very simple molecules, or some elements, or both.<br />

3) Single displacement: This is when one element trades places with another element in a<br />

compound. These reactions come in the general form of:<br />

One example of a single displacement reaction is when magnesium replaces hydrogen in water to<br />

make magnesium hydroxide and hydrogen gas:<br />

Mg + 2 H2O ---> Mg(OH)2 + H2<br />

If a pure element reacts with another compound (usually, but not always, ionic), it’s probably a single<br />

displacement reaction. The products will be the compounds formed when the pure element switches<br />

places with another element in the other compound.<br />

Important note: these reactions will only occur if the pure element on the reactant side of the equation<br />

is higher on the activity series than the element it replaces.


87<br />

4) Double displacement: This is when the anions and cations of two different molecules<br />

switch places, forming two entirely different compounds. These reactions are in the general form:<br />

One example of a double displacement reaction is the reaction of lead (II) nitrate with potassium<br />

iodide to form lead (II) iodide and potassium nitrate:<br />

Pb(NO3)2 + 2 KI ---> PbI2 + 2 KNO3<br />

If two ionic compounds combine, it’s probably a double displacement reaction. Switch the cations<br />

and balance out the charges to figure out what will be made.<br />

Important note: These reactions will only occur if both reactants are soluble in water and only one<br />

product is soluble in water.<br />

5) Acid-base: This is a special kind of double displacement reaction that takes place when an<br />

acid and base react with each other. The H + ion in the acid reacts with the OH - ion in the base,<br />

causing the formation of water. Generally, the product of this reaction is some ionic salt and water:<br />

One example of an acid-base reaction is the reaction of hydrobromic acid (HBr) with sodium<br />

hydroxide:<br />

HBr + NaOH ---> NaBr + H2O<br />

If an acid and a base combine, it’s an acid-base reaction. The products will be an ionic compound<br />

and water.<br />

6) Combustion: A combustion reaction is when oxygen combines with another compound to<br />

form water and carbon dioxide. These reactions are exothermic, meaning they produce heat. An<br />

example of this kind of reaction is the burning of napthalene:<br />

C10H8 + 12 O2 ---> 10 CO2 + 4 H2O<br />

If something that has carbon and hydrogen reacts with oxygen, it’s probably a combustion reaction.<br />

The products will be CO2 and H2O.<br />

Follow this series of questions. When you can answer "yes" to a question, then<br />

stop!<br />

1) Does your reaction have two (or more) chemicals combining to form one chemical? If yes, then it's<br />

a synthesis reaction<br />

2) Does your reaction have one large molecule falling apart to make several small ones? If yes, then<br />

it's a decomposition reaction<br />

3) Does your reaction have any molecules that contain only one element? If yes, then it's a single<br />

displacement reaction<br />

4) Does your reaction have water as one of the products? If yes, then it's an acid-base reaction<br />

5) Does your reaction have oxygen as one of it's reactants and carbon dioxide and water as<br />

products? If yes, then it's a combustion reaction<br />

6) If you haven't answered "yes" to any of the questions above, then you've got a double<br />

displacement reaction.


List what type the following reactions are:<br />

1) NaOH + KNO3 --> NaNO3 + KOH<br />

Double Displacement<br />

2) CH4 + 2 O2 --> CO2 + 2 H2O<br />

Combustion<br />

3) 2 Fe + 6 NaBr --> 2 FeBr3 + 6 Na<br />

Single displacement<br />

4) CaSO4 + Mg(OH)2 --> Ca(OH)2 + MgSO4<br />

Double displacement<br />

5) NH4OH + HBr --> H2O + NH4Br<br />

Acid-Base<br />

6) Pb + O2 --> PbO2<br />

Synthesis<br />

7) Na2CO3 --> Na2O + CO2<br />

Decomposition<br />

88


89<br />

Determine the Type of Reaction for each equation.<br />

Then predict the products of each of the following chemical reactions. If a reaction will not occur,<br />

explain why not.<br />

Then Balance the equation.<br />

Double Displacement<br />

1) __Ag2SO4 + __NaNO3 2 → _2_AgNO^3+__Na(^2)SO^4<br />

Ag 2<br />

(SO^4) 1<br />

Na 1 *2= Na 2<br />

(NO^3) 1 *2= (NO^3) 2<br />

Ag 1 *2= Ag 2<br />

(SO^4) 1<br />

Na 2<br />

(NO^3) 1 *2= (NO^3) 2<br />

2) __NaI 2 + __CaSO4 →<br />

Na 1 *2= Na 2<br />

I 1 *2= I 2<br />

Ca 1<br />

S 1<br />

O 4<br />

3) __HNO3 + __Ca(OH)2 →<br />

H 3 +1 = H 4<br />

N 1 *2 = N 2<br />

O 5 +3 = O 8<br />

Ca 1<br />

Double Displacement = __(Na^2)I+__CaI^2<br />

Acid-Base -> _2_ H^2O+ __Ca(NO^3)^2<br />

H 2 *2 = H 4<br />

N 2<br />

O 7 +1 = O 8<br />

Ca 1<br />

Na 2<br />

I 2<br />

Ca 1<br />

S 1<br />

O 4<br />

4) __CaCO3 →<br />

Ca 1<br />

C 1<br />

O 3<br />

Decomposition = __CaO+__CO^2<br />

Ca 1<br />

C 1<br />

O 3<br />

5) __AlCl3 + __(NH4)PO4 → Double Displacement = __Al(PO^4)+_3_(NH^4)Cl<br />

Al 1<br />

Cl 3<br />

NH^4 3<br />

PO^4 1<br />

^3<br />

Al 1<br />

Cl 3<br />

NH^4 3<br />

PO^4 1<br />

6) __Pb + __Fe(NO3)3 → Not possible due to Lead (Pb) being less reactive than Iron (Fe)<br />

7) __C3H6 2 + __O2 9 →<br />

C 3 *2 = C 6<br />

H 6 *2 = H 12<br />

O 2 *9 = O 18<br />

Combustion= _6_H^2O+_6_CO^2<br />

C 1 *3 = C 3 *2 = C 6<br />

H 2 *3= H 6 *2 = H 12<br />

O 3 +10= O 13+5 = O 18<br />

8) __Na 2 + __CaSO4 →<br />

Single displacement = __Ca+__(Na^2)SO^4<br />

Na 1 *2= Na 2<br />

Ca 1<br />

S 1<br />

O 4<br />

Na 2<br />

Ca 1<br />

S 1<br />

O 4


How to Balance Chemical Equations<br />

A chemical equation is a theoretical or written representation of what happens during a chemical<br />

reaction. The law of conservation of mass states that no atoms can be created or destroyed in a<br />

chemical reaction, so the number of atoms that are present in the reactants has to balance the<br />

number of atoms that are present in the products. Follow this guide to learn how to balance chemical<br />

equations.<br />

Step 1<br />

Write down your given equation. For this example, we will use:<br />

C3H8 + O2 --> H2O + CO2<br />

Step 2<br />

Write down the number of atoms that you have on each side of the equation. Look at the subscripts<br />

next to each atom to find the number of atoms in the equation.<br />

Left side: 3 carbon, 8 hydrogen and 2 oxygen<br />

Right side: 1 carbon, 2 hydrogen and 3 oxygen<br />

90


91<br />

Step 3<br />

Always leave hydrogen and oxygen for last. This means that you will need to balance the carbon<br />

atoms first.<br />

Step 4<br />

Add a coefficient to the single carbon atom on the right of the equation to balance it with the 3 carbon<br />

atoms on the left of the equation.<br />

C3H8 + O2 --> H2O + 3CO2<br />

The coefficient 3 in front of carbon on the right side indicates 3 carbon atoms just as the subscript 3<br />

on the left side indicates 3 carbon atoms.<br />

In a chemical equation, you can change coefficients, but you should never alter the subscripts.


Step 5<br />

Balance the hydrogen atoms next. You have 8 on the left side, so you'll need 8 on the right side.<br />

C3H8 + O2 --> 4H2O + 3CO2<br />

On the right side, we added a 4 as the coefficient because the subscript showed that we already<br />

had 2 hydrogen atoms.<br />

When you multiply the coefficient 4 times the subscript 2, you end up with 8.<br />

Step 6<br />

Finish by balancing the oxygen atoms.<br />

Because we've added coefficients to the molecules on the right side of the equation, the number of<br />

oxygen atoms has changed. We now have 4 oxygen atoms in the water molecule and 6 oxygen<br />

atoms in the carbon dioxide molecule. That makes a total of 10 oxygen atoms.<br />

Add a coefficient of 5 to the oxygen molecule on the left side of the equation. You now have 10<br />

oxygen molecules on each side.<br />

C3H8 + 5O2 --> 4H2O + 3CO2.<br />

The carbon, hydrogen and oxygen atoms are balanced. Your equation is complete.<br />

92


1) ___ 2 NaNO3 + ___ PbO ___ Pb(NO3)2 + ___ Na2O<br />

Na 1 *2= Na 2<br />

N 1 *2= N 2<br />

O 4 +3= O7<br />

Pb 1 -> Pb 1<br />

Na 2<br />

N 2<br />

O 7<br />

Pb 1<br />

2) ___ 6 AgI + ___ Fe2(CO3)3 ___ 2 FeI3 + ___ 3 Ag2CO3<br />

Ag 1 *6= Ag 6<br />

I 1 *6= I 6<br />

Fe 2<br />

CO^3 3 / (C 3) (O 9)<br />

Ag 2 *3= Ag 6<br />

I 3 *2= I 6<br />

Fe 1 *2= Fe 2<br />

(CO^3) 1 *3= CO^3 3 / (C 3) (O 9)<br />

3) ___ C2H4O2 + ___ 2 O2 ___ 2 CO2 + ___ 2 H2O<br />

C 2<br />

H 4<br />

O 4 +2= O 6<br />

C 1 *2= C 2<br />

H 2 *2= H 4<br />

O 3 +1+2= O 6<br />

4) ___ ZnSO4 + ___ Li2CO3 ___ ZnCO3 + ___ Li2SO4<br />

Zn 1<br />

S 1<br />

Li 2<br />

C 1<br />

O 7<br />

Zn 1<br />

S 1<br />

Li 2<br />

C 1<br />

O 7<br />

5) ___ V2O5 + ___ 5 CaS ___ 5 CaO + ___ V2S5<br />

V 2<br />

O 5<br />

Ca 1<br />

93


94<br />

6) ___ Mn(NO2)2 + ___ BeCl2 ___ Be(NO2)2 + ___ MnCl2<br />

Mn 1<br />

N 2<br />

O 4<br />

Be 1<br />

Cl 2<br />

Mn 1<br />

N 2<br />

O 4<br />

Be 1<br />

Cl 2<br />

7) 3___ AgBr + ___ GaPO4 ___ Ag3PO4 + ___ GaBr3<br />

Ag 1 *3 = Ag 3<br />

Br 1 *3 = Br 3<br />

Ga 1<br />

P 1<br />

O 4<br />

Ag 3<br />

Br 3<br />

Ga 1<br />

P 1<br />

O 4<br />

8) ___ 3 H2SO4 + ___ 2 B(OH)3 __ B2(SO4)3 + ___ 6 H2O<br />

H 5 +4 = H 9 +3 = H 12<br />

S 1 *3 = S 3<br />

O 7 +8 = O 15+ 3= O 18<br />

B 1 *2 = B 2<br />

H 2 *6 = H 12<br />

S 3<br />

O 13 +5 = O 18<br />

B 2<br />

9) ___ S8 + ___ 8 O2 ___ 8 SO2<br />

S 8<br />

O 2 *8 = O 16<br />

S 1 *8 = S 8<br />

O 2 *8 = O 16<br />

10) ___ Fe + ___ 2 AgNO3 ___ Fe(NO3)2 + ___ 2 Ag<br />

Fe 1<br />

Ag 1 *2 = Ag 2<br />

N 1 *2 = N 2<br />

O 3 *2 = O 6<br />

Fe 1<br />

Ag 1 *2 = Ag 2<br />

N 1 *2= N 2<br />

O 3 *2= O 6


1) 2 NaNO3 + PbO Pb(NO3)2 + Na2O<br />

2) 6 AgI + Fe2(CO3)3 2 FeI3 + 3 Ag2CO3<br />

3) C2H4O2 + 2 O2 2 CO2 + 2 H2O<br />

4) ZnSO4 + Li2CO3 ZnCO3 + Li2SO4<br />

5) V2O5 + 5 CaS 5 CaO + V2S5<br />

6) Mn(NO2)2 + BeCl2 Be(NO2)2 + MnCl2<br />

7) 3 AgBr + GaPO4 Ag3PO4 + GaBr3<br />

8) 3 H2SO4 + 2 B(OH)3 B2(SO4)3 + 6 H2O<br />

9) S8 + 8 O2 8 SO2<br />

10) Fe + 2 AgNO3 Fe(NO3)2 + 2 Ag<br />

Additional Notes:<br />

95


The Learning Goal for this assignment is: Apply the mole concept and the law of conservation of mass to calculate<br />

quantities of chemicals particicpating in reactions<br />

Stoichiometry and Balancing Reactions<br />

Stoichiometry is a section of chemistry that involves using relationships between reactants and/or<br />

products in a chemical reaction to determine desired quantitative data. In Greek, stoikhein means<br />

element and metron means measure, so stoichiometry literally translated means the measure of<br />

elements. In order to use stoichiometry to run calculations about chemical reactions, it is important to<br />

first understand the relationships that exist between products and reactants and why they exist, which<br />

require understanding how to balanced reactions.<br />

Balancing<br />

In chemistry, chemical reactions are frequently written as an equation, using chemical symbols. The<br />

reactants are displayed on the left side of the equation and the products are shown on the right, with<br />

the separation of either a single or double arrow that signifies the direction of the reaction. The<br />

significance of single and double arrow is important when discussing solubility constants, but we will<br />

not go into detail about it in this module. To balance an equation, it is necessary that there are the<br />

same number of atoms on the left side of the equation as the right. One can do this by raising the<br />

coefficients.<br />

Reactants to Products<br />

A chemical equation is like a recipe for a reaction so it displays all the ingredients or terms of a<br />

chemical reaction. It includes the elements, molecules, or ions in the reactants and in the products as<br />

well as their states, and the proportion for how much of each particle is create relative to one another,<br />

through the stoichiometric coefficient. The following equation demonstrates the typical format of a<br />

chemical equation:<br />

2Na(s) + 2HCl(aq) → 2NaCl(aq) + H2(g)<br />

In the above equation, the elements present in the reaction are represented by their chemical<br />

symbols. Based on the Law of Conservation of Mass, which states that matter is neither created nor<br />

destroyed in a chemical reaction, every chemical reaction has the same elements in its reactants and<br />

products, though the elements they are paired up with often change in a reaction. In this reaction,<br />

sodium (Na), hydrogen (H), and chloride (Cl) are the elements present in both reactants, so based on<br />

the law of conservation of mass, they are also present on the product side of the equations.<br />

Displaying each element is important when using the chemical equation to convert between<br />

elements.<br />

Stoichiometric Coefficients<br />

In a balanced reaction, both sides of the equation have the same number of elements. The<br />

stoichiometric coefficient is the number written in front of atoms, ion and molecules in a chemical<br />

reaction to balance the number of each element on both the reactant and product sides of the<br />

equation. These stoichiometric coefficients are useful since they establish the mole ratio between<br />

reactants and products. In the balanced equation:<br />

2Na(s)+2HCl(aq)→2NaCl(aq)+H2(g)<br />

96


we can determine that 2 moles of HCl will react with 2 moles of Na(s) to form 2 moles of NaCl(aq) and 1<br />

mole of H2(g). If we know how many moles of Na we start out with, we can use the ratio of 2 moles<br />

of NaCl to 2 moles of Na to determine how many moles of NaCl were produced or we can use the<br />

ration of 1 mole of H2 to 2 moles of Na to convert to NaCl. This is known as the coefficient factor. The<br />

balanced equation makes it possible to convert information about one reactant or product to<br />

quantitative data about another element. Understanding this is essential to solving stoichiometric<br />

problems.<br />

Example 1<br />

Lead (IV) hydroxide and sulfuric acid react as shown below. Balance the reaction.<br />

Solution<br />

___Pb(OH)4 +___H2SO4→___Pb(SO4)2 +___H2O<br />

Start by counting the number of atoms of each element.<br />

Unbalanced<br />

Pb 1 1 Pb<br />

O 8 9 O<br />

H 6 2 H<br />

S 1 2 S<br />

The reaction is not balanced; the reaction has 16 reactant atoms and only 14 product atoms and does<br />

not obey the conservation of mass principle. Stoichiometric coefficients must be added to make the<br />

equation balanced. In this example, there are only one sulfur atom present on the reactant side, so a<br />

coefficient of 2 should be added in front of H2SO4to have an equal number of sulfur on both sides of<br />

the equation. Since there are 12 oxygen on the reactant side and only 9 on the product side, a 4<br />

coefficient should be added in front of H2O where there is a deficiency of oxygen. Count the number<br />

of elements now present on either side of the equation. Since the numbers are the same, the<br />

equation is now balanced.<br />

Pb(OH)4 + 2H2SO4→ Pb(SO4)2 + 4H2O<br />

Balanced<br />

Pb 1 1 Pb<br />

O 8 12 12 9 O<br />

H 6 8 8 2 H<br />

S 1 2 2 2 S<br />

Balancing reactions involves finding least common multiples between numbers of elements present<br />

on both sides of the equation. In general, when applying coefficients, add coefficients to the<br />

molecules or unpaired elements last.<br />

A balanced equation ultimately has to satisfy two conditions.<br />

1. The numbers of each element on the left and right side of the equation must be equal.<br />

2. The charge on both sides of the equation must be equal. It is especially important to pay<br />

attention to charge when balancing redox reactions.<br />

97


Stoichiometry and Balanced Equations<br />

In stoichiometry, balanced equations make it possible to compare different elements through the<br />

stoichiometric factor discussed earlier. This is the mole ratio between two factors in a chemical<br />

reaction found through the ratio of stoichiometric coefficients. Here is a real world example to show<br />

how stoichiometric factors are useful.<br />

Example 2<br />

There are 12 party invitations and 20 stamps. Each party invitation needs 2 stamps to be sent. How<br />

many party invitations can be sent?<br />

Solution<br />

The equation for this can be written as<br />

I+2S→IS2<br />

where<br />

I represent invitations,<br />

S represents stamps, and<br />

IS 2 represents the sent party invitations consisting of one invitation and two stamps.<br />

<br />

Based on this, we have the ratio of 2 stamps for 1 sent invite, based on the balanced equation.<br />

Invitations Stamps Party Invitations Sent<br />

In this example are all the reactants (stamps and invitations) used up? No, and this is normally the<br />

case with chemical reactions. There is often excess of one of the reactants. The limiting reagent, the<br />

one that runs out first, prevents the reaction from continuing and determines the maximum amount of<br />

product that can be formed.<br />

Example 3<br />

What is the limiting reagent in this example?<br />

Solution<br />

Stamps, because there was only enough to send out invitations, whereas there were enough<br />

invitations for 12 complete party invitations. Aside from just looking at the problem, the problem can<br />

be solved using stoichiometric factors.<br />

12 I x 1IS2 = 12 IS2 possible<br />

1I<br />

20 S x 1IS2 = 10 IS2 possible<br />

2S<br />

98


When there is no limiting reagent because the ratio of all the reactants caused them to run out at the<br />

same time, it is known as stoichiometric proportions.<br />

Types of Reactions<br />

There are 6 basic types of reactions.<br />

Combustion: Combustion is the formation of CO2 and H2O from the reaction of a chemical<br />

and O2<br />

Combination (synthesis): Combination is the addition of 2 or more simple reactants to form a<br />

complex product.<br />

Decomposition: Decomposition is when complex reactants are broken down into simpler<br />

products.<br />

Single Displacement: Single displacement is when an element from on reactant switches with<br />

an element of the other to form two new reactants.<br />

Double Displacement: Double displacement is when two elements from on reactants<br />

switched with two elements of the other to form two new reactants.<br />

Acid-Base: Acid- base reactions are when two reactants form salts and water.<br />

Molar Mass<br />

Before applying stoichiometric factors to chemical equations, you need to understand molar mass.<br />

Molar mass is a useful chemical ratio between mass and moles. The atomic mass of each individual<br />

element as listed in the periodic table established this relationship for atoms or ions. For compounds<br />

or molecules, you have to take the sum of the atomic mass times the number of each atom in order to<br />

determine the molar mass.<br />

Example 4<br />

What is the molar mass of H2O?<br />

Solution<br />

Molar mass = 2 × (1.00g/mol) + 1×(16.0g/mol) = 18.0g/mol<br />

Using molar mass and coefficient factors, it is possible to convert mass of reactants to mass of<br />

products or vice versa.<br />

Example 5: Combustion of Propane<br />

Propane (C3H8) burns in this reaction:<br />

C3H8 + 5O2 → 4H2O + 3CO2<br />

If 200 g of propane is burned, how many g of H2Ois produced?<br />

Solution<br />

Steps to getting this answer: Since you cannot calculate from grams of reactant to grams of products<br />

you must convert from grams of C3H8 to moles of C3H8 then from moles of C3H8 to moles of H2O.<br />

Then convert from moles of H2O to grams of H2O.<br />

99


Step 1: 200g C3H8 is equal to 4.54 mol C3H8.<br />

Step 2: Since there is a ratio of 4:1 H2O to C3H8, for every 4.54 mol C3H8 there are 18.18 mol<br />

H2O.<br />

Step 3: Convert 18.18 mol H2O to g H2O 18.18 mol H2O is equal to 327.27 g H2O.<br />

Variation in Stoichiometric Equations<br />

Almost every quantitative relationship can be converted into a ratio that can be useful in data<br />

analysis.<br />

Density<br />

Density (ρ) is calculated as mass/volume. This ratio can be useful in determining the volume of a<br />

solution, given the mass or useful in finding the mass given the volume. In the latter case, the inverse<br />

relationship would be used.<br />

Volume x (Mass/Volume) = Mass<br />

Mass x (Volume/Mass) = Volume<br />

Percent Mass<br />

Percent establishes a relationship as well. A percent mass states how many grams of a mixture are of<br />

a certain element or molecule. The percent X% states that of every 100 grams of a mixture, X grams<br />

are of the stated element or compound. This is useful in determining mass of a desired substance in<br />

a molecule.<br />

Example 6<br />

A substance is 5% carbon by mass. If the total mass of the substance is 10.0 grams, what is the<br />

mass of carbon in the sample? How many moles of carbon are there?<br />

Solution<br />

10 g sample x 5 g carbon = 0.5 g carbon<br />

100 g sample<br />

0.5g carbon x 1 mol carbon = 0.0416 mol carbon<br />

12.0g carbon<br />

Molarity<br />

Molarity (moles/L) establishes a relationship between moles and liters. Given volume and molarity, it<br />

is possible to calculate mole or use moles and molarity to calculate volume. This is useful in chemical<br />

equations and dilutions.<br />

100


Example 7<br />

How much 5M stock solution is needed to prepare 100 mL of 2M solution?<br />

Solution<br />

100 mL of dilute solution (1 L/1000 mL) (2 mol/1L solution) (1 L stock solution/5 mol solution) (1000<br />

ml stock solution/1L stock solution) = 40 mL stock solution.<br />

These ratios of molarity, density, and mass percent are useful in complex examples ahead.<br />

Determining Empirical Formulas<br />

An empirical formula can be determined through chemical stoichiometry by determining which<br />

elements are present in the molecule and in what ratio. The ratio of elements is determined by<br />

comparing the number of moles of each element present.<br />

Example 8<br />

1. Find the molar mass of the empirical formula CH2O.<br />

12.0g C + (1.00g H) * (2H) + 16.0g O = 30.0 g/mol CH2O<br />

2. Determine the molecular mass experimentally. For our compound, it is 120.0 g/mol.<br />

3. Divide the experimentally determined molecular mass by the mass of the empirical formula.<br />

(120.0 g/mol) / (30.0 g/mol) = 3.9984<br />

4. Since 3.9984 is very close to four, it is possible to safely round up and assume that there was a<br />

slight error in the experimentally determined molecular mass. If the answer is not close to a whole<br />

number, there was either an error in the calculation of the empirical formula or a large error in the<br />

determination of the molecular mass.<br />

5. Multiply the ratio from step 4 by the subscripts of the empirical formula to get the molecular<br />

formula.<br />

CH2O * 4 =?<br />

C: 1 * 4 = 4<br />

H: 2 * 4 = 8<br />

O 1 * 4 = 4<br />

CH2O * 4 = C4H8O4<br />

6. Check your result by calculating the molar mass of the molecular formula and comparing it to the<br />

experimentally determined mass.<br />

molar mass of C4H8O4= 120.104 g/mol<br />

experimentally determined mass = 120.056 g/mol<br />

% error = | theoretical - experimental | / theoretical * 100%<br />

% error = | 120.104 g/mol - 120.056 g/mol | / 120.104 g/mol * 100%<br />

% error = 0.040 %<br />

101


Stoichiometry and balanced equations make it possible to use one piece of information to calculate<br />

another. There are countless ways stoichiometry can be used in chemistry and everyday life. Try and<br />

see if you can use what you learned to solve the following problems.<br />

Problem 1<br />

Why are the following equations not considered balanced?<br />

a. H2O(l)→H2(g)+O2(g) There are not the same amount of Oxygens on the reactants side as the products side<br />

b. Zn(s)+Au + (aq) →Zn 2+ (aq) +Ag(s)<br />

There are not the same elements on the reactants and products side<br />

Problem 2<br />

Hydrochloric acid reacts with a solid chunk of aluminum to produce hydrogen gas and aluminum ions.<br />

Write the balanced chemical equation for this reaction.<br />

6 _HCl + 2 _Al = 3 _H^2 + 2 _AlCl^3<br />

H 1 -> H 6<br />

Cl 1 -> Cl 6<br />

Al 1 -> Al 2<br />

H 2 -> H 6<br />

Cl 3 -> Cl 6<br />

Al 1 -> Al 2<br />

Problem 3<br />

Given a 10.1M stock solution, how many mL must be added to water to produce 200 mL of 5M<br />

solution?<br />

Problem 4<br />

If 0.502g of methane gas react with 0.27g of oxygen to produce carbon dioxide and water, what is the<br />

limiting reagent and how many moles of water are produced? The unbalanced equation is provided<br />

below.<br />

CH4(g)+O2(g)→CO2(g)+H2O(l)<br />

102


Theoretical and Actual Yields<br />

Key Terms<br />

<br />

<br />

<br />

(Excess reagent, limiting reagent)<br />

Theoretical and actual yields<br />

Percentage or actual yield<br />

Skills to Develop<br />

Use stoichiometric calculation to determine excess and limiting reagents in a chemical reaction<br />

<br />

<br />

and explain why.<br />

Calculate theoretical yields of products formed in reactions that involve limiting reagents.<br />

Evaluate percentage or actual yields from known amounts of reactants<br />

Theoretical and Actual Yields<br />

Reactants not completely used up are called excess reagents, and the reactant that completely<br />

reacts is called the limiting reagent. This concept has been illustrated for the reaction:<br />

2Na+Cl2 →2NaCl<br />

Amounts of products calculated from the complete reaction of the limiting reagent are called<br />

theoretical yields, whereas the amount actually produced of a product is the actual yield. The ratio of<br />

actual yield to theoretical yield expressed in percentage is called the percentage yield.<br />

percent yield = actual yield / theoretical yield ×100<br />

Chemical reaction equations give the ideal stoichiometric relationship among reactants and products.<br />

Thus, the theoretical yield can be calculated from reaction stoichiometry. For many chemical<br />

reactions, the actual yield is usually less than the theoretical yield, understandably due to loss in the<br />

process or inefficiency of the chemical reaction.<br />

Example 1<br />

Methyl alcohol can be produced in a high-pressure reaction<br />

CO(g) + 2H2(g) →CH3OH(l)<br />

If 6.1 metric tons of methyl alcohol is obtained from 1.2 metric tons of hydrogen reacting with excess<br />

amount of CO, estimate the theoretical and the percentage yield?<br />

Hint:<br />

To calculate the theoretical yield, consider the reaction<br />

CO(g) + 2H2(g) → CH3OH(l)<br />

28.0 + 4.0 = 32.0 (stoichiometric masses in, g, kg, or tons)<br />

1.2 tons H2 × 32.0 CH3OH = 9.6 tons CH3OH<br />

4.0 H2<br />

Thus, the theoretical yield from 1.2 metric tons (1.2x10 6 g) of hydrogen gas is 9.6 tons. The actual<br />

yield is stated in the problem, 6.1 metric tons. Thus, the percentage yield is<br />

103


%yield = 6.1 tons × 100 = 64%<br />

9.6tons<br />

Discussion<br />

Due to chemical equilibrium or the mass action law, the limiting reagent may not be completely<br />

consumed. Thus, a lower yield is expected in some cases. Losses during the recovery process of the<br />

product will cause an even lower actual yield.<br />

Example 2<br />

A solution containing silver ion, Ag + , has been treated with excess of chloride ions Cl − . When dried,<br />

0.1234 g of AgCl was recovered. Assuming the percentage yield to be 98.7%, how many grams of<br />

silver ions were present in the solution?<br />

Hint:<br />

The reaction and relative masses of reagents and product are:<br />

The calculation,<br />

Ag + (aq) + Cl − (aq) → AgCl(s)<br />

107.868 + 35.453 = 143.321<br />

0.1234 g AgCl ×107.868 g Ag + =0.09287 g Ag +<br />

143.321g AgCl<br />

shows that 0.1234 g dry AgCl comes from 0.09287g Ag + ions. Since the actual yield is only 98.7%,<br />

the actual amount of Ag + ions present is therefore<br />

0.09287 g Ag + = 0.09409 g Ag +<br />

0.987<br />

Discussion<br />

One can also calculate the theoretical yield of AgCl from the percentage yield of 98.7% to be<br />

0.1234 g AgCl =0.1250 g AgCl<br />

0.987<br />

From 0.1250 g AgCl, the amount of Ag + present is also 0.09409 g.<br />

Stoichiometry - A Review<br />

Skills Taught<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

evaluate molecular weight for a given formula<br />

evaluate weight (mass) percentages of elements for a given formula<br />

evaluate amounts (in mass and mole units) produced in a chemical reaction from given<br />

conditions<br />

classify reactions by types: combination, combustion, displacement, formation, etc<br />

determine the chemical formula when weight percentages are given and then evaluate the<br />

mole percentages of elements in the formula<br />

determine the chemical formula when weight percentages are given and molecular weight is<br />

known<br />

determine the amount produced, the actual yield, and other stoichiometry quantities for a given<br />

reaction<br />

104


Review Purposes<br />

<br />

<br />

<br />

<br />

<br />

To get an overall view of stoichiometry.<br />

Apply skills learned to perform quantitative chemical analysis.<br />

Apply theories and rules of chemistry to solve problems.<br />

Assess areas of strength and weakness for review purposes.<br />

Improve problem solving strategy and learning efficiency.<br />

Stoichiometry<br />

STOICHIOMETRY is the quantitative relationship of reactants and products. This unit has been<br />

divided into the following objects. A brief review is given here so that you can get a birds'-eye or<br />

overall view of stoichiometry.<br />

1.Amounts of substances<br />

Express amounts of substance in mass units of g, kg, tons, and convert them to moles,<br />

kilomoles, or millimoles.<br />

2.Chemical formulas<br />

Represent a substance with a formula that reflects its chemical composition, structure, and<br />

bonding; evaluate weight and mole percentages of elements in a substance; and determine<br />

chemical formula by elemental analysis.<br />

3.Reaction features<br />

Define some common features of chemical reactions; classify chemical reactions by common<br />

features such as combination, combustion, decomposition, displacement, and redox reactions.<br />

4.Reaction equations<br />

Express quantitative relationships using chemical reaction equations; evaluate quantities of<br />

reactants and products in a chemical reaction; and solve reaction stoichiometry problems.<br />

5.Excess and limiting reagents<br />

Define excess and limiting reagents; determine excess and limiting reagents in a reaction<br />

mixture; and determine quantities produced in a chemical reaction.<br />

6.Yields<br />

Define theoretical and actual yields due to limiting reagent; apply the concept of limiting<br />

reagent to evaluate theoretical yield; convert actual yield to percentage yields.<br />

105


Use the space provided to write out the steps you take to solve different types of problems.<br />

Use any additional space for notes. These 2 pages should be full when you turn in your notebook.<br />

Steps to solve problems<br />

Mole to Mole:<br />

(*in a balanced equation, everything on both sides is equal to each other as a ratio)<br />

(1) In the equation: _H^2+_O^2 -> _H^2O , If you are given 6 moLs of H^2, how many moLs of O^2 will react with it?<br />

1. Balance the equation: _2_H^2+ _1_O^2 -> _2_H^2O<br />

2. Take what you are given (in this case, 6 moLs of O^2) and convert to what you need it to be through the balanced equatio<br />

____________________<br />

6 moL H^2 I 1 moL O^2<br />

2 moL H^2<br />

3. Multiply across the bottom and top -> 6__<br />

2<br />

-> 3 moL O^2<br />

4. Match significant figures (in this case, we already have the appropriate amount of significant figures)<br />

The answer is: 3 moLs of O^2<br />

Mass to Mole:<br />

(*in a balanced equation, everything on both sides is equal to each other as a ratio)<br />

(1) For the balanced equation shown below, how many moles of H^2 will be produced by 53.5grams of Al?<br />

_2_Al+_3_H^2SO^4=>_1_Al^2(SO^4)^3+_3_H^2<br />

1. Take what you are given (in this case, 53.3 g of Al) and convert to what you need it to be through mole:mole<br />

and mole:mass ratios<br />

2. Take the grams (53.5g of Al) and figure out the molar mass of the compound, so you know how much is 1 moL<br />

(*use the average mass of the element found on the periodic table to find molar mass of the element)<br />

Al = 27amu, therefore, 27g of Al = 1 moL Al<br />

3. Convert the given mass to moLs through the balanced equation<br />

53.5 _________________<br />

g Al // 1 moL Al<br />

27 g Al<br />

4. Now convert to the unit that you want to end with (in this case, moLs of H^2)<br />

53.5 _____________________________<br />

g Al // 1 moL Al // 3 moL H^2<br />

27 g Al 2 moL Al<br />

5. Multiply across the top and the bottom and then divide to find the amount you're looking for in moLs<br />

_____________________________<br />

53.5 g Al // 1 moL Al // 3 moL H^2<br />

27 g Al 2 moL Al<br />

-><br />

160.5 ____<br />

54<br />

-> 2.9722222222 moL of H^2<br />

6. Apply significant figures<br />

2.9722222222 moL of H^2 -> (only 3 significant figures were given at the beginning of the problem) -> 2.97 moL of H^2<br />

The answer would be: 2.97 moLs of H^2<br />

106


Moles to Mass: (*in a balanced equation, everything on both sides is equal to each other as a ratio)<br />

(1) For the balanced equation shown below, how many grams of S reacted, if 0.147moles of Al^2S^3 are produced?<br />

_2_Al+_3_S=>_1_Al^2S^3<br />

1. Take the amount you are given (in this case, 0.147 moL Al^2S^3) and convert to moLs of the desired element<br />

(through the balanced equation given)<br />

0.147 _____________________________<br />

moL Al^2S^3 // 3 moL S<br />

1 moL Al^2S^3<br />

2. Take the moLs of the substance you've converted to (3 moLs of S), and turn those into grams (the desired unit = grams of S)<br />

___________________________________________<br />

0.147 moL Al^2S^3 // 3 moL S // 32 g of S<br />

1 moL Al^2S^3 // 1 moL of S<br />

3. Multiply across the top and the bottom<br />

___________________________________________ 0.147 moL Al^2S^3 // 3 moL S // 32 g of S<br />

-><br />

1 moL Al^2S^3 // 1 moL of S<br />

14.112 ______<br />

1<br />

-> 14.112 g of S<br />

4. Apply significant figures<br />

14.112 g of S -> (only 3 significant figures given at the beginning of the problem) -> 14.1 g of S<br />

The answer is : 14.1 g of S<br />

Mass to Mass:<br />

(*in a balanced equation, everything on both sides is equal to each other as a ratio)<br />

(1) For the balanced equation shown below, how many grams of Al will react with 12.4 grams of Al2O3?<br />

_2_Al+_3_MnO=>_1_Al^2O^3+_3_Mn<br />

1. Take the amount you are given (in this case, 12.4g Al^2O^3) and convert to the moLs of the compound<br />

^<br />

(*find the molar mass of the compound so you can convert)<br />

Al 2 * 27<br />

O 3 * 16<br />

^<br />

amount of the element you have<br />

54+48= 102g/moL Al^2O^3<br />

12.4g __________________________<br />

Al^2O^3 // 1 moL Al^2O^3<br />

// 102 g Al^2O^3<br />

2. Convert to the desired element/compound through mole:mole ratios (in this case, to moLs of Al through the balanced equation)<br />

__________________________________________<br />

12.4g Al^2O^3 // 1 moL Al^2O^3 // 2 moL Al<br />

// 102 g Al^2O^3 // 1 moL Al^2O^3<br />

3. Find the mass of the desired element through conversion of the mole<br />

___________________________________________________<br />

12.4g Al^2O^3 // 1 moL Al^2O^3 // 2 moL Al // 27g Al<br />

// 102 g Al^2O^3 // 1 moL Al^2O^3 // 1 moL Al<br />

4. Multiply across the top and the bottom, then divide.<br />

___________________________________________________ 12.4g Al^2O^3 // 1 moL Al^2O^3 // 2 moL Al // 27g Al -><br />

// 102 g Al^2O^3 // 1 moL Al^2O^3 // 1 moL Al<br />

_____ 669.6<br />

102<br />

-> 6.564705882 g Al -> (*apply sig. fig.) -> 6.56 g Al<br />

107


Unit 6<br />

Chapter 13 States of Matter<br />

The students will learn what are the factors that determine and<br />

characteristics that distinguish gases liquids and solids and<br />

how substances change from one state to another.<br />

Differentiate among the four states of matter.<br />

Students will measure the physical characteristics of matter such as temperature<br />

and density.<br />

Students will compare and contrast the physical characteristics of the 4 states of<br />

matter.<br />

solid<br />

liquid<br />

gas<br />

plasma<br />

Relate temperature to the average molecular kinetic energy.<br />

Students will be able to compare and contrast the motion of particles of a sample<br />

at various temperatures.<br />

Kinetic energy<br />

Kinetic theory<br />

Temperature<br />

Describe phase transitions in terms of kinetic molecular theory.<br />

Students will be able to identify and describe phase changes.<br />

Students will be able to compare and contrast the change in particle motion<br />

for phase changes.<br />

Students will be able to interpret heating/cooling curves and phase diagrams.<br />

melting point<br />

freezing point<br />

boiling point<br />

condensation<br />

sublimation<br />

phase diagram<br />

kinetic molecular theory<br />

108


Chapter 14 The Behavior of Gases<br />

The students will learn how gases respond to changes in<br />

pressure, volume, and temperature and why the ideal gas law<br />

is useful even though ideal gases do not exist.<br />

Interpret the behavior of ideal gases in terms of kinetic molecular theory.<br />

Students will be able to describe the behavior of an ideal gas.<br />

Students will participate in activities to apply the Ideal Gas Law and its<br />

component laws to predict gas behavior.<br />

Students will be able to perform temperature/pressure conversions.<br />

Compressibility<br />

Boyle’s Law<br />

Charles’s Law<br />

Gay-Lussac’s Law<br />

Combine Gas Law<br />

Ideal Gas Law<br />

Partial pressure<br />

Dalton’s Law of partial pressure<br />

Diffusion<br />

Effusion<br />

Graham’s Law of effusion<br />

Chapter 15 Water and Aqueous Systems<br />

The students will learn how the interactions between water<br />

molecules account for the unique properties of water and how<br />

aqueous solutions form.<br />

Discuss the special properties of water that contribute to Earth's suitability<br />

as an environment for life: cohesive behavior, ability to moderate<br />

temperature, expansion upon freezing, and versatility as a solvent.<br />

Students will be able to prepare a solution of known molarity<br />

Students will participate in activities to calculate molarity<br />

Surface tension<br />

Surfactant<br />

Aqueous solutionSolvent<br />

Solute<br />

109


The Learning Goal for this assignment is: Differentiate among the four states of matter.<br />

Take note over the following chapter. Use the Headings provided to organize your notes. Define and number all highlighted vocabulary (total 23 ) as well<br />

as summarize the sections. You may add pictures where needed. The pictures should be an appropriate size. Use Arial 12 for all text. This document<br />

should be 3 pages and should be saved as a pdf before you submit it into Angel.<br />

13.1 The Nature of Gases<br />

Chapter 13 States of Matter<br />

Pages 420 - 439<br />

Kinetic Theory and a Model for Gases – kinetic energy 1 : an object’s energy due to motion<br />

Kinetic theory 2 : all matter is made of tiny particles that constantly move<br />

Summary: Gas particles are small hard spheres that are largely spread apart with empty space<br />

between them, but the particles in a gas bounce around wildly and randomly, and they also never<br />

lose energy when colliding.<br />

Connection: Gas is just spastically bouncing everywhere because of its kinetic energy and not losing<br />

energy when it collides against other gas particles.<br />

Gas Pressure – gas pressure 3 : the force a gas exerts against a unit of surface area of an object<br />

Vacuum 4 : a void empty of particles and pressure<br />

Atmospheric pressure 5 : the collision of objects and atoms/molecules in the air<br />

Barometer 6 : a device used to measure atmospheric pressure<br />

Pascal (Pa) 7 : The SI unit of pressure<br />

Standard atmosphere (atm) 8 : the pressure necessary to push 760 mm of mercury up a barometer at<br />

25°C<br />

Summary: Gas pressure results from billions of gas particles colliding against objects, which also<br />

creates atmospheric pressure by colliding against objects in the earth’s atmosphere. There are<br />

different ways to measure atmospheric pressure, one being the barometer, which uses mercury being<br />

pushed up a tube by the air colliding against it (atmospheric pressure). The modern (SI) unit of<br />

pressure is the pascal (Pa), which is only a small amount of pressure, so often times they use<br />

kilopascals (100 kPa = 100,000 Pa). The older measures of pressure are the millimeters of mercury<br />

(mm Hg) and standard atmosphere (atm). The conversion rate is as follows:<br />

1 atm = 760 mm Hg = 101.3 kPa<br />

Connection: Basically, the reason we’re able to breathe is because Earth’s gravity keeps atoms in<br />

the atmosphere, and then they collide against each other creating atmospheric pressure, weather and<br />

all that good stuff.<br />

Kinetic Energy and Temperature –<br />

Summary: Kinetic energy is just absorbed energy that speeds up the movement of a particle, and the<br />

rest of that absorbed energy is potential energy. All substances have the same average kinetic<br />

energy at any given temperature. A substance’s temperature is directly related to average kinetic<br />

energy, shown by how when temperature increases or decreases, average kinetic energy rises or<br />

falls. The theory of absolute zero, the coldest temperature possible (0K), says there is no movement<br />

whatsoever in particles, but scientists have only achieved 0.1 nanokelvin (0.1x10 -9 K), and only seen<br />

the coldest part of space being at 1K. Kelvin temperatures are directly related to average kinetic<br />

energy, and something at a higher Kelvin temperature has more kinetic energy than something at a<br />

lower Kelvin temperature.<br />

110


Connection: This is why when liquid nitrogen (which is naturally a gas) touches other objects, it<br />

evaporates and turns to gas, but the object it touches freezes, because the nitrogen’s kinetic energy<br />

increases and the object it is touching loses kinetic energy.<br />

13.2 The Nature of Liquids<br />

A Model of Liquids – Summary: Liquids are fluids, substances that can flow, and the particles are<br />

attracted to each other and stay close together, keeping the volume of a liquid definite. The<br />

characteristics of liquids are determined by the irregular movements/flow of the particles and the<br />

attraction of the particles which keeps the liquid together. The way water fills a bottle and bounces<br />

around inside the bottle, but settles and stays together is an example of this. Liquids’ close particles<br />

means that there is more density in a liquid than a gas, making it known as a condensed state of<br />

matter.<br />

Evaporation – vaporization 9 : the conversion of liquid to gas or vapor<br />

Evaporation 10 : the process of vaporization occurring at the surface of a liquid that is not boiling<br />

Summary: Vaporization is liquids turning into gas or a vapor, and evaporation is vaporization of a<br />

liquid that isn’t boiling. Evaporation occurs when molecules reach a certain minimum kinetic energy to<br />

break free from the surface of the liquid, but those same molecules can be bounced back by air and<br />

returned to the liquid if they don’t have enough kinetic energy. If a liquid is heated, it is more likely to<br />

evaporate, as particles at the surface gain more kinetic energy, making it easier to escape the liquid’s<br />

surface. This kinetic energy leaving the liquid makes the average kinetic energy of the liquid lower,<br />

therefore cooling it.<br />

Connection: Plants drying out in hot temperatures makes sense because as water evaporates to try<br />

to cool the plant, if the heat is too much, the plant loses all its water trying to cool off and dries out.<br />

Vapor Pressure – Vapor pressure 11 : The force a gas exerts above a liquid<br />

Summary: Liquid in a closed container gets vaporized and then bounces off of the container’s walls<br />

creating vapor pressure. The particles eventually condense again and go through condensation to<br />

return to being a liquid. Once the rates of evaporation and condensation are equivalent, there is a<br />

constant vapor pressure, meaning that the amount of particles that are liquid and vapor remain<br />

constant.<br />

Connection: this explains why my fish tank, whenever it wasn’t filled with water, would start fogging<br />

up when we didn’t have the AC on and my fish wouldn’t exactly do the best, so we’d turn the AC on to<br />

cool the house and the water level would return to normal<br />

Boiling Point – Boiling point (bp) 12 : when vapor pressure of the liquid is equal to external pressure<br />

on the liquid<br />

Normal boiling point 13 : the boiling point of a liquid at standard atmosphere/101.3 kPa<br />

Summary: Heating a liquid adds more kinetic energy, and when there is enough kinetic energy<br />

throughout a liquid to turn to vapor, it boils. Boiling points also change at different altitudes, because<br />

atmospheric pressure changes. At lower external pressure, there’s less kinetic energy necessary to<br />

boil, and more kinetic energy necessary for higher external pressure. Boiling is a cooling process like<br />

evaporation, but the temperature of the boiling liquid never changes, the temperature change only<br />

increases the rate of boiling. Liquids can have various boiling points at different pressures.<br />

Connection: We boil water every morning, and I’ve found that the steam hurts more than the actual<br />

boiling water (don’t ask why I’d dunk my hand in boiling water) and the textbook explains it as the<br />

steam having more potential energy than the water itself.<br />

13.3 The Nature of Solids<br />

A Model of Solids – Melting point (mp) 14 : the temperature a solid changes into a liquid<br />

111


Freezing point 15 : the temperature a liquid turns to a solid<br />

Summary: Solids are compact and dense, and vibrate around a fixed point instead of flowing. When<br />

they’re heated to have enough kinetic energy, they melt and start to flow, and the substance turns<br />

into a liquid. The same for a liquid losing kinetic energy, the atoms stop slowing and condense,<br />

known as freezing, and they become a solid.<br />

Connection: The first time I saw snow, freezing and melting actually started making sense, because<br />

snow when it gets slushier and starts melting, and “flows” under my feet when I crush it. Then it got<br />

colder and the snow was denser, so it just broke apart.<br />

Crystal Structure and Unit Cell – Crystal 16 : a solid substance arranged in an orderly and<br />

repeating 3D pattern.<br />

Unit cell <strong>17</strong> : the smallest group of particles that retain the geometric shape of a crystal.<br />

Allotropes 18 : two or more different forms of the same element in the same physical state<br />

Amorphous solid 19 : a solid without an ordered internal structure<br />

Glass 20 : clear fusion of inorganic substances that cooled without becoming crystal<br />

Summary: Most solids are crystals, which are organized and repeating molecular geometric<br />

structures. Crystal have sides/faces, and are organized into seven groups, known as crystal systems.<br />

A crystals shape is dependent on the arrangement of its particles. Solid substances can exist in more<br />

than one form, such as carbon, which can be a diamond, graphite, and have other solid forms as well.<br />

Allotropes are two different forms of the same element in the same state, but have different properties<br />

because their structures are different. There are also non-crystalline solids which have the properties<br />

of a solid, but amorphous solids don’t maintain an organized structure. Glass is like a liquid in the<br />

case that its atom structure sort of flows, but is also organized as a solid. It doesn’t melt either, it just<br />

softens when it is heated. When it’s shattered it has jagged edges and irregular angles, unlike<br />

crystalline solids.<br />

13.4 Changes of State<br />

Sublimation – sublimation 21 : The change from solid to gas without becoming a liquid<br />

Summary: Solids with vapor pressures higher than atmospheric pressure at room temperature go<br />

through sublimation, the change from solid to gas without becoming a liquid. One example of this is<br />

dry ice, the solid form of carbon dioxide, which is used to cool and refrigerate other substances. It<br />

goes directly from solid to gas, because its temperature is -78 o C. Sublimation is used in many other<br />

products, and also used by chemists to separate mixtures and purify compounds.<br />

Phase Diagrams – phase diagram 22 : a table giving the points of temperature and pressure that a<br />

substance exists at a solid, liquid, or gas.<br />

Triple point 23 : the only set of conditions where all three states of matter of a substance can exist in<br />

equilibrium with one another.<br />

Summary: The relationships between solid, liquid, and gas (vapor) can be represented on a phase<br />

diagram, which uses temperature and pressure to indicate relationships between states of matter.<br />

Solid lines on a phase diagram represent points of temperature and pressure that two states of matter<br />

are in equilibrium, and there is a point where all three exist in equilibrium, called the triple point. By<br />

referring to a phase diagram, you can relate all the pressures and temperatures of the three states of<br />

matter of a substance and view when they all exist in equilibrium.<br />

Connection: Using phase diagrams you can see the points where substances like Iodine go through<br />

sublimation, or when a liquid like mercury would exist as a solid or gas.<br />

112


Name: Leonardo Gutierrez<br />

Name: Joel Jones<br />

Grade:<br />

States of Matter Project<br />

You and you lab partner are going to create a study aid in the form of a game for the<br />

information in Chapter 13 States of Matter.<br />

First, each of you, independently from each other, will summarize the chapter on 3<br />

pages of a pdf which will be submitted in Angel by the end of class on Wednesday Feb<br />

22.<br />

Second, you and you lab partner will be given a game platform which you will use for<br />

your questions and answers, either Jeopardy or Kahoot.<br />

Third, you will fill in the information at the bottom of this page with your username,<br />

passwords and/or websites so that you do not forget this and I have a copy in case<br />

anything gets misplaced. This page will be submitted into Angel as a Word Document<br />

on Wednesday February 22 during class.<br />

Fourth, you will use your notes to generate the questions and answers.<br />

Finally you will give me access to your game by putting the website or Game Number<br />

on this page adding this page to your 3 pages of notes and resubmitting it in Angel as<br />

a pdf by the end of the class on Friday Feb 24.<br />

This page is due by the end of class on Wednesday February 22.<br />

This Project is due by the end of class on Friday February 24.<br />

Jeopardy (https://jeopardylabs.com)<br />

Password:<br />

Edit Link:<br />

Play Link:<br />

Kahoot (https://getkahoot.com)<br />

Username: leongutz<br />

Email: leonardo.gutierrez.lwths@gmail.com<br />

Password: MustangLG<br />

Game PIN:<br />

113


Temperature/Average<br />

Kinetic Energy<br />

Pressure<br />

Volume<br />

Gas laws help us to predict, if given a certain scenario, the temperature,<br />

pressure, and volume of something, and how changing the temperature,<br />

volume, or pressure will impact other variables.<br />

114


As pressure increases, volume must decrease. If volume increases,<br />

pressure must decrease. (For a constant temperature and mass)<br />

Inital pressure & volume<br />

115


Constant Mass & Pressure<br />

Volume and temperature (in Kelvin) change, and they both<br />

increase and decrease at the same rate.<br />

116


Constant Volume and Mass<br />

Pressure is directly related to Kelvin temperature.<br />

It increases/decreases at the same rate. (Vice Versa)<br />

1<strong>17</strong>


118


119


120


121


Combined Gas Law:<br />

Through the combination of Boyle’s, Charles’, and Gay Lussac’s Law,<br />

we end up with this law. Both pressure and volume have a directly<br />

proportional realtionship to temperature, but an inverse relation with<br />

each other, and this law ends up as this formula:<br />

P1V1 =P2V2<br />

T 1 T 2<br />

A gas has a volume of 800.0 mL at minus 23.00 °C and 300.0 torr. What<br />

would the volume of the gas be at 227.0 °C and 600.0 torr of pressure?<br />

122


Ideal Gas Law:<br />

To figure out how many particles are inside a gas system,<br />

as well as the volume, pressure, and temperature of said<br />

system, you take the pressure and volume of the gas, and<br />

know how many particles there are by knowing A.) How<br />

many moles are in the system, B.) The ratio of pressure to<br />

moles by Kelvin (P/[mole*kelvin’]), and C.) The<br />

temperature of the system. The formula is:<br />

P*V=nRT<br />

P=Pressure V=Volume n= # of moles R=Gas Constant<br />

T=Temp. in K<br />

You have 10 mol of a Gas at 30 o C, occupying a 0.5 L<br />

container. What is the pressure of the gas in atmospheres?<br />

123


The Learning Goal for this assignment is:<br />

The students will learn how the interactions between water molecules account for the unique<br />

properties of water and how aqueous solutions form.<br />

Take note over the following chapter. Use the Headings provided to organize your notes. Define and number all highlighted vocabulary (total 22 ) as well<br />

as summarize and take notes over the sections. You may add pictures where needed. The pictures should be an appropriate size. Use Arial 12 for all<br />

text. This document should be 2 pages and should be saved as a pdf before you submit it into Angel.<br />

Chapter 15 Water and Aqueous Systems<br />

Pages 488 - 507<br />

15.1 Water and Its Properties<br />

Water in the Liquid State – Water, H2O, is a polar molecule comprised of two hydrogens on<br />

either side of an oxygen. This polarity results in hydrogen bonding, which attributes water many of its<br />

unique properties (high surface tension, low vapor pressure, high boiling point). Water molecules are<br />

drawn towards the inside of a water droplet, creating a spherical shape, and the force that pulls a<br />

liquid inward and makes liquids have smaller surface areas is called surface tension 1 . Water has a<br />

higher surface tension than most liquids, but its surface tension decreases when you add a<br />

surfactant 2 , which is any substance that interferes with the hydrogen bonding between water<br />

molecules (which causes beads of water to spread out/flatten). That’s why when you add soap (a<br />

surfactant) to water, the droplets are flatter than normal. Hydrogen bonding in water creates a low<br />

vapor pressure because all of the hydrogen bonds keep the liquid connected, so the bonds have to<br />

be broken in order to allow for molecules to escape and evaporate (and the chances of that are low,<br />

so evaporation happens slowly.) Otherwise, a glass of water would start to disappear the moment you<br />

pour it. Hydrogen bonding is also strong enough to keep it from boiling at standard temperature,<br />

otherwise it would be a gas at normal temperatures on Earth.<br />

Water in the Solid State – Water as a solid is less dense than as a liquid, so ice floats in water.<br />

Hydrogen bonds hold water molecules in place at the solid phase, and the structure is arranged<br />

hexagonally with an open framework. The structure of a snowflake is similar to that of an ice crystal.<br />

In liquid water, molecules are more packed together, which makes it denser than ice because ice’s<br />

structural arrangement keeps it spread apart. Ice floating at the top of a body of water acts as an<br />

insulator for the rest of a body of water, meaning that the water at the bottom is above 0 oC , creating<br />

conditions for organisms to live below the water. Ice melts at a relatively high temperature for its low<br />

density, meaning that it takes a lot of energy to get ice to melt, whereas the same amount of energy<br />

raises the temperature of liquid water rapidly. (That’s why ice in your drink keeps your drink cool for<br />

so long. The energy that would heat up water quickly is instead absorbed by ice cubes, keeping your<br />

drink cool.)<br />

15.2 Homogeneous Aqueous Systems<br />

Solutions – You won’t find pure water in nature because water dissolves many substances it comes<br />

in contact with, and water with dissolved substances inside is known as an aqueous solution 3 .<br />

Solutions are comprised of a solvent 4 , which is the substance doing the dissolving, and the dissolved<br />

particles in a solvent are a solute 5 , and they are dispersed in the solvent. Solutions are stable<br />

homogenous mixtures, meaning that they don’t settle out when resting (given that conditions like<br />

temperature are constant), and that both the solvent and solute pass through filters. Ionic and polar<br />

covalent compounds dissolve easily inside of water, but nonpolar covalent compounds do not. Water<br />

molecules are constantly moving, and when an ionic solid is placed inside water, the water molecules<br />

124


collide into it. This process of the positive and negative ions of an ionic solid being surrounded by a<br />

solvent is known as solvation 6 . Some crystals have stronger attractions between ions inside the<br />

crystal than with water, so they barely dissolve, and are nearly insoluble. Nonpolar substances can’t<br />

be dissolved in polar substances, but can be dissolved in nonpolar solvents. (This is why oil and<br />

water don’t mix, but oil in gasoline creates a solution.) Polar dissolves polar, and nonpolar dissolves<br />

nonpolar.<br />

Electrolytes and Nonelectrolytes – Electrolytes 7 are compounds that conduct electricity in<br />

aqueous solutions or in the molten state. This requires ions, meaning that all ionic compounds are<br />

electrolytes. (This is why they give you saline, a water salt mixture, in the hospital, so that electricity in<br />

your body conducts easily.) Nonelectrolytes 8 are compounds that don’t conduct electricity in either<br />

an aqueous or molten state, and in many materials, this is due to not containing ions. Although, not all<br />

electrolytes conduct electricity the same. Strong electrolytes 9 have all or nearly all of the solute<br />

comprised of ions, like sodium chloride (Salt/NaCl). On the other hand, weak electrolytes 10 conduct<br />

electricity poorly because a smaller portion of the compound is comprised of ions.<br />

Hydrates – Water can be contained in crystals, and that water is known as water of hydration 11 . A<br />

compound that contains water of hydration is known as a hydrate 12 . Water is easily lost and regained<br />

in hydrates because of the weak forces holding the water in hydrates. Substances that do not contain<br />

water are anhydrous 13 . Hydrates often have weaker vapor pressure due to weak forces holding the<br />

water, so if the vapor pressure of the hydrate is higher than that of the air, the water will effloresce 14 ,<br />

and lose its water of hydration. Hydrated ionic compounds with a low vapor pressure will remove<br />

water from the air in order to make higher hydrate, and these are known as hygroscopic 15 .<br />

Substances that absorb water from the air and create a dry atmosphere are dessicants 16 . The<br />

dessicant calcium chloride is used to keep substances dry, as it absorbs the moisture from other<br />

substances while not dissolving them, or being dissolved. They can return to their anhydrous state by<br />

being heated. Some compounds are so hygroscopic that they become wet in normal moist air, and<br />

they take enough water to fully dissolve and become solutions, and they are known as<br />

deliquescent <strong>17</strong> .<br />

15.3 Heterogeneous Aqueous Systems<br />

Suspensions – A suspension 18 is a mixture in which particles settle once they’re left sitting.<br />

Suspensions differ from solutions due to their particles being much larger and not staying suspended.<br />

Suspensions are heterogeneous, because at least two substances can be found, and can often be<br />

separated by filtering. The same concept can be applied to the ocean, and although you can see<br />

sand being moved and suspended by waves, it still eventually settles to the bottom.<br />

Colloids – Colloids 19 are heterogeneous mixtures with particles of different sizes (1nm-1000nm).<br />

The particles are spread throughout the substance, and it can be a gas, liquid or solid. One example<br />

is milk, and that’s why when you shine a light a glass of milk, the light doesn’t reach through the other<br />

side, because all the suspended particles block the light from passing through. Colloids have particles<br />

smaller than suspensions but larger than solutions. Colloids can be differentiated between using the<br />

Tyndall effect 20 , which is the scattering of light by colloidal particles. When studied under a<br />

microscope, particles scattering/reflecting light move erratically, and cause flashes of light called<br />

scintillations. This erratic movement is called Brownian motion 21 . Colloidal particles stay suspended<br />

through the absorption of +/- ions, and although the colloid itself stays neutral, the particles gain<br />

charges through absorption, and they don’t clump together because of all the opposite charges<br />

around each particle. Colloids can be liquids dispersed in other liquids, and these are known as<br />

emulsions 22 . They are created with emulsifying agents, which allow for liquids to be suspended in<br />

each other.<br />

125


Unit 7<br />

Chapter 16 Solutions<br />

The students will learn what properties are used to describe<br />

the nature of solutions and how to quantify the concentration<br />

of a solution.<br />

Chapter <strong>17</strong> Thermochemistry<br />

The student will learn how energy is converted in a chemical<br />

or physical process and how to determine the amount of<br />

energy is absorbed or released in that process.<br />

Differentiate among the various forms of energy and recognize that they can<br />

be transformed from one form to others.<br />

Students will participate in activities to investigate and describe the<br />

transformation of energy from one form to another (i.e. batteries, food, fuels,<br />

etc.)<br />

Explore the Law of Conservation of Energy by differentiating among open,<br />

closed, and isolated systems and explain that the total energy in an isolated<br />

system is a conserved quantity.<br />

<br />

Students will be able to calculate various energy changes:<br />

o q = mc∆t<br />

o ∆Hfus<br />

o ∆Hmelt<br />

Thermochemistry<br />

Heat<br />

System<br />

Surrounding<br />

Law of conservation of energy<br />

Bond Making is exothermic<br />

Bond Breaking is endothermic<br />

Heat capacity<br />

Specific heat<br />

Calorimetry<br />

Enthalpy<br />

Thermochemical equation<br />

Molar heat of (fusion, solidification,<br />

vaporization, condensation, solution)<br />

Distinguish between endothermic and exothermic chemical processes.<br />

Students will be able to recognize exothermic and endothermic reactions through<br />

experimentation.<br />

Students will participate in activities (Pasco) to create exothermic and<br />

endothermic graphs.<br />

Endothermic<br />

Exothermic<br />

126


Create and interpret potential energy diagrams, for example: chemical<br />

reactions, orbits around a central body, motion of a pendulum<br />

Students will participate in activities (Pasco) to create exothermic and<br />

endothermic graphs.<br />

Students will be able to interpret exothermic and endothermic reaction graphs.<br />

Potential energy diagram<br />

Thermochemical equations<br />

Chapter 18 Reaction Rates and Equilibrium<br />

The student will learn how the rate of a chemical reaction can<br />

be controlled, what the role of energy is and why some<br />

reactions occur naturally and others do not.<br />

Explain how various factors, such as concentration, temperature, and<br />

presence of a catalyst affect the rate of a chemical reaction.<br />

Students will be able to describe how each factor may affect the rate of a<br />

chemical reaction.<br />

Students will be able to compare the relative effect of each factor on the rate of a<br />

chemical reaction.<br />

Rate<br />

Collision theory<br />

Activation energy<br />

Catalyst<br />

Activated complex<br />

Inhibitor<br />

Explain the concept of dynamic equilibrium in terms of reversible processes<br />

occurring at the same rates.<br />

Students will be able to describe a system in dynamic equilibrium.<br />

Students will be able to describe how factors may affect the equilibrium of a<br />

reaction.<br />

Reversible reaction<br />

Chemical equilibrium<br />

Le Chatelier principle<br />

Explain entropy’s role in determining the efficiency of processes that convert<br />

energy to work.<br />

Students will be able to describe the change in entropy of a reaction.<br />

Students will be able to determine if a reaction is spontaneous<br />

Entropy<br />

Law of disorder<br />

Spontaneous/nonspontaneous reaction<br />

127


The Learning Goal for this assignment is:<br />

students will learn what properties are used to describe the nature of solutions<br />

how to quantify the concentration of a solution.<br />

Defining Concentration<br />

Measures of Concentration<br />

Concentration is defined as the amount of dissolved solute in a given amount of solvent or<br />

solution. There are several terms that describe concentration. Some of these terms are relative;<br />

that is, they can be used only to compare the concentration of one solution to another. Dilute and<br />

concentrated are two such terms. A dilute solution contains less dissolved solute than a<br />

concentrated solution (in equal volumes of solution).<br />

The terms saturated, unsaturated, and supersaturated are terms that describe concentration more<br />

precisely.<br />

<br />

<br />

<br />

<br />

<br />

<br />

Saturated: The maximum amount of solute is dissolved in a given amount of solvent at a<br />

particular temperature. Such solutions are stable.<br />

Unsaturated: Less than the maximum amount of solute is dissolved in a given amount of<br />

solvent at a particular temperature. Such solutions are stable.<br />

Supersaturated: More than the maximum amount of solute is dissolved in a given amount of<br />

solvent at a particular temperature. Such solutions are unstable.<br />

Look at the solubility curve shown below:<br />

The solubility of NaNO3 is 86.0 g/100 mL H2O (at 20 °C). If you<br />

prepare a solution of 50.0 g NaNO3 dissolved in 100 mL H2O, an unsaturated solution results<br />

(Point A on the graph).<br />

continue adding NaNO to the solution until 86.0 g are dissolved, a saturated solution results<br />

(Point B).<br />

heat the solution to 50 °C, 113 grams NaNO3 can be dissolved (Point C). When the solution<br />

cools back down to 20 °C, it will be supersaturated (Point D).<br />

Quantifying Concentration<br />

To describe the concentration of a solution even more precisely, various measures of concentration<br />

can be used. Some of the ways concentration can be quantified include calculating the<br />

Mass of solute per solution mass (expressed as a percent or parts per million)<br />

Moles of solute per kilogram solvent (molality)<br />

Mass of solute per liter of solution (grams/liter)<br />

Moles of solute per liter of solution (molarity)<br />

128


Part 1: Mass Percent<br />

Mass percent (also called percent by mass, weight percent, or percent by weight) compares the<br />

mass of the solute to the entire mass of the solution.<br />

Notes:<br />

This is just the percentage of solute that makes up the entire solution, hence why you multiply by 100<br />

Part 2: Parts per Million<br />

Parts per million (ppm) is another measure of concentration. It is similar to mass percent. But<br />

mass percent indicates the number of grams of solute per 100 g solution. Parts per million<br />

indicates the number of grams of solute per 1,000,000 g solution. This measure of concentration is<br />

often used to express the concentrations of very dilute solutions.<br />

Notes:<br />

This is pretty much the same thing as mass percent, but in a much larger quantity of actual solution<br />

Part 3: Molality<br />

Molality (m) is the ratio of the moles of solute to the kilograms of solvent. Note: this is the first<br />

measure of concentration that is concerned with the mass of the solvent, not the mass of the<br />

solution as a whole.<br />

Notes:<br />

This is a comparison between the moles of the solute to the actual mass of the solvent (in Kg) instead of the whole solution<br />

Part 4: Grams per Liter<br />

To express the concentration of a solution in grams per liter, you must know the mass of the solute<br />

and the volume of the solution, not just the volume of the solvent.<br />

Notes:<br />

This is a comparison between the mass of the solvent and how much of the volume of the solution it takes up<br />

Suppose you wanted to know what the concentration would be before making the solution. Could that<br />

be done? In order to relate the volume or mass of solvent to the volume of solution, you would have<br />

to know the density of the solution. You will see how solution density can be used to calculate<br />

molarity in the next section.<br />

129


Part 5: Molarity<br />

Molarity (M) is the most common measure of concentration. The concentration of most solutions<br />

you see in the lab are expressed in terms of molarity. Just like g/L, molarity calculations require<br />

that you know either the volume or density of the resulting solution.<br />

Notes:<br />

Like molality, this is instead the amount of moles of solute filling up the volume in Liters of the solution<br />

Using Density to Calculate Molarity<br />

If the volume of the resulting solution is not known, molarity is calculated as follows:<br />

Convert the volume of solvent to grams. (The simulation does this step for you.)<br />

Determine the total mass of the solution (mass of solute + mass of solvent).<br />

Convert the solution mass to volume in milliliters, using its density (volume = mass / density).<br />

Convert the solution volume to liters (divide by 1000).<br />

Convert solute grams to moles.<br />

Calculate the molarity (moles solute / L solution).<br />

Reinforcing What You've Learned<br />

1. 35.0 g potassium dichromate are dissolved in 354.0 g distilled water. What is the concentration<br />

of the resulting solution, expressed as percent by mass? 9.00%<br />

2. A chemist discovers that 2587.0 g distilled water are contaminated with 13.0 g NaNO3. What is<br />

the concentration of NaNO3, expressed in ppm? 5.00 X 10 3<br />

3. <strong>17</strong>5.00 g H2SO4 are added to 61.49 g distilled H2O. What is the molality of the resulting solution?<br />

29.04m<br />

4. 225 g NaBr are dissolved in 525 g distilled water. If the volume of the resulting solution is<br />

584 mL, what is its concentration when expressed in g/L? 385g/L<br />

5. 470.0 g Na2CO3 are dissolved in 4230.0 g distilled water. What is the molarity of the resulting<br />

solution (D = 1.1029 g/mL)? 1.1561 M<br />

Applying What You've Learned<br />

6. Think about the equations for mass percent and parts/million. Consider how you might convert<br />

between these two measures of concentration.<br />

Mass percent = ppm ÷ 10,000 ppm = mass percent X .0001<br />

7. Think about the equations for grams/liter and molarity. Consider how you might convert<br />

between these two measures of concentration.<br />

grams / L = molarity X molar mass<br />

molarity = grams / L ÷ molar mass<br />

130


Glossary<br />

Concentration: Amount of dissolved solute in a given amount of solvent or solution.<br />

Density: Amount of matter per unit volume. Density is calculated by dividing an object's mass by<br />

its volume.<br />

Mass: Amount of matter an object contains or, more scientifically, the measure of an object's<br />

resistance to changes in motion. The SI (Systéme International) unit for mass is the kilogram. In<br />

the lab, mass is often measured in grams.<br />

Mass percent: Also referred to as percent by mass and, occasionally, weight percent or percent<br />

by weight. Mathematically, mass % = (mass of solute / mass of entire solution) x 100.<br />

Molar mass: Mass of a compound, calculated by adding up the individual masses for its component<br />

atoms, which are obtained from the periodic table of the elements. Molar mass is expressed in<br />

grams/mole and is sometimes referred to as molecular mass (for molecular compounds) or formula<br />

mass (for ionic compounds).<br />

Molality (m): Moles of solute per kilogram of solvent. Mathematically, m = moles of solute / kilogram of<br />

solvent.<br />

Molarity (M): Moles of solute per liter of solution. Mathematically, M = moles of solute / liter of<br />

solution.<br />

Mole (mol): Counting unit used to express the large numbers of particles, such as atoms or<br />

molecules, that are involved in chemical processes. One mole of particles contains 6.02 x 10<br />

particles. The mass of one mole of an element, in grams, is equivalent to the atomic mass for that<br />

element, as indicated on the periodic table.<br />

Parts per million (ppm): Measure of concentration often used for dilute solutions. Mathematically,<br />

ppm = (mass of solute / mass of solution) x 10.<br />

Solubility: Measure of the maximum amount of solute that can be dissolved in a given amount of<br />

solvent at a given temperature, forming a stable solution.<br />

Solute: Dissolved substance in a solution. The solute is generally the solution component present<br />

in the lesser amount.<br />

Solution: Homogeneous mixture in which one substance has been dissolved in another.<br />

Solvent: Substance in which a solute is dissolved to form a solution. The solvent is generally the<br />

solution component present in the greater amount.<br />

Volume: Amount of space an object occupies. The SI (Systéme International) unit for volume is<br />

the cubic meter. In the lab, volume is often measured in cubic centimeters, milliliters, or liters.<br />

SAS Curriculum Pathways VLab #866<br />

131


The Learning Goal for this assignment is:<br />

The student will learn how energy is converted in a<br />

chemical or physical process and how to determine the<br />

amount of energy is absorbed or released in that process.<br />

The System and the Surroundings in <strong>Chemistry</strong><br />

Thermochemistry<br />

The system is the part of the universe we wish to focus our attention on. In the world of chemistry, the<br />

system is the chemical reaction. For example:<br />

2H2 + O2 ---> 2H2O<br />

The system consists of those molecules which are reacting.<br />

The surroundings are everything else; the rest of the universe. For example, say the above reaction is<br />

happening in gas phase; then the walls of the container are part of the surroundings.<br />

There are two important issues:<br />

1. a great majority of our studies will focus on the change in the amount of energy, not the<br />

absolute amount of energy in the system or the surroundings.<br />

2. regarding the direction of energy flow, we have a "sign convention."<br />

Two possibilities exist concerning the flow of energy between system and surroundings:<br />

1. The system can have energy added to it, which increases its amount and lessens the energy<br />

amount in the surroundings.<br />

2. The system can have energy removed from it, thereby lowering its amount and increasing the<br />

amount in the surroundings.<br />

We will signify an increase in energy with a positive sign and a loss of energy with a negative sign.<br />

Also, we will take the point-of-view from the system. Consequently:<br />

1. When energy (heat or work) flow out of the system, the system decreases in its amount. This<br />

is assigned a negative sign and is called exothermic.<br />

2. When energy (heat or work) flows into the system, the system increases its energy amount.<br />

This is assigned a positive sign and is called endothermic.<br />

We do not discuss chemical reactions from the surrounding's point-of-view. Only from the system's.<br />

Notes:<br />

The system is what chemistry focuses on, and the system is where the reaction (&the molecules involved) takes<br />

place. Our studies focus on the change of energy and the direction of energy flow. represented by the "sign<br />

convention". The system can either have energy added (endothermic) or removed (exothermic) from it, which<br />

removes or releases energy from/to the surroundings.<br />

132


Specific Heat<br />

Here is the definition of specific heat:<br />

the amount of heat necessary for 1.00 gram of a substance to change 1.00 °C<br />

Note the two important factors:<br />

1. It's 1.00 gram of a substance<br />

2. and it changes 1.00 °C<br />

Keep in mind the fact that this is a very specific value. It is only for one gram going one degree. The<br />

specific heat is an important part of energy calculations since it tells you how much energy is needed<br />

to move each gram of the substance one degree.<br />

Every substance has its own specific heat and each phase has its own distinct value. In fact, the<br />

specific heat value of a substance changes from degree to degree, but we will ignore that.<br />

The units are often Joules per gram-degree Celsius (J/g*°C). Sometimes the unit J/kg K is also used.<br />

This last unit is technically the most correct unit to use, but since the first one is quite common, you<br />

will need to know both.<br />

I will ignore calorie-based units almost entirely.<br />

Here are the specific heat values for water:<br />

Phase J g¯1 °C¯1 J kg¯1<br />

K¯1<br />

Gas 2.02 2.02 x 10 3<br />

Liquid 4.184 4.184 x 10 3<br />

Solid 2.06 2.06 x 10 3<br />

Notice that one set of values is simply 1000 times bigger than the other. That's to offset the influence<br />

of going from grams to kilograms in the denominator of the unit.<br />

Notice that the change from Celsius to Kelvin does not affect the value. That is because the specific<br />

heat is measured on the basis of one degree. In both scales (Celsius and Kelvin) the jump from one<br />

degree to the next are the same "distance." Sometimes a student will think that 273 must be involved<br />

somewhere. Not in this case.<br />

Specific heat values can be looked up in reference books. Typically, in the classroom, you will not be<br />

asked to memorize any specific heat values. However, you may be asked to memorize the values for<br />

the three phases of water.<br />

As you go about the Internet, you will find different values cited for specific heats of a given<br />

substance. For example, I have seen 4.186 and 4.187 used in place of 4.184 for liquid water. None of<br />

the values are wrong, it's just that specific heat values literally change from degree to degree. What<br />

happens is that an author will settle on one particular value and use it. Often, the one particular value<br />

used is what the author used as a student.<br />

Hence, 4.184.<br />

133


The Time-Temperature Graph<br />

We are going to heat a container that has 72.0 grams of ice (no liquid water yet!) in it. To make the<br />

illustration simple, please consider that 100% of the heat applied goes into the water. There is no loss<br />

of heat into heating the container and no heat is lost to the air.<br />

Let us suppose the ice starts at -10.0 °C and that the pressure is always one atmosphere. We will<br />

end the example with steam at 120.0 °C.<br />

There are five major steps to discuss in turn before this problem is completely solved. Here they are:<br />

1. the ice rises in temperature from -10.0 to 0.00 °C.<br />

2. the ice melts at 0.00 °C.<br />

3. the liquid water then rises in temperature from zero to 100.0 °C.<br />

4. the liquid water then boils at 100.0 °C.<br />

5. the steam then rises in temperature from 100.0 to 120.0 °C<br />

Each one of these steps will have a calculation associated with it. WARNING: many homework and<br />

test questions can be written which use less than the five steps. For example, suppose the water in<br />

the problem above started at 10.0 °C. Then, only steps 3, 4, and 5 would be required for solution.<br />

To the right is the type of graph which is typically used to<br />

show this process over time.<br />

You can figure out that the five numbered sections on the<br />

graph relate to the five numbered parts of the list just above<br />

the graph.<br />

Also, note that numbers 2 and 4 are phases changes: solid<br />

to liquid in #2 and liquid to gas in #4.<br />

Q=mcΔT<br />

where ΔT is (Tf – Ti)<br />

Here are some symbols that will be used, A LOT!!<br />

Δt = the change in temperature from start to finish in degrees Celsius (°C)<br />

m = mass of substance in grams<br />

c = the specific heat. Its unit is Joules per gram X degree Celsius (J / g °C is one way to write<br />

the unit; J g¯1 °C¯1 is another)<br />

q = the amount of heat involved, measured in Joules or kilojoules (symbols = J and kJ)<br />

mol = moles of substance.<br />

ΔH is the symbol for the molar heat of fusion and ΔH is the symbol for the molar heat of<br />

vaporization.<br />

We will also require the molar mass of the substance. In this example it is water, so the molar mass is<br />

18.0 g/mol.<br />

Notes:<br />

The specific heat of a substance is the heat required to raise 1 gram of said substance by 1 degree Celsius.<br />

The process of ice melting/freezing and steam evaporaing/condensing is separate from the temperature change equation<br />

because the ice/water/steam is gaining energy while changing phase, but not changing in temperature,<br />

The equation for the calculation of a substance changing temperature without going through a phase change applies the<br />

specific heat of that substance, which varies on which state the substance is in.<br />

134


Step One: solid ice rises in temperature<br />

As we apply heat, the ice will rise in temperature until it<br />

arrives at its normal melting point of zero Celsius.<br />

Once it arrives at zero, the Δt equals 10.0 °C.<br />

Here is an important point: THE ICE HAS NOT MELTED<br />

YET.<br />

At the end of this step we have SOLID ice at zero<br />

degrees. It has not melted yet. That's an important point.<br />

Each gram of water requires a constant amount of energy<br />

to go up each degree Celsius. This amount of energy is<br />

called specific heat and has the symbol c.<br />

72.0 grams of ice (no liquid water yet!) has changed 10.0 °C. We need to calculate the energy<br />

needed to do this.<br />

This summarizes the information needed:<br />

Δt = 10 °C<br />

The mass = 72.0 g<br />

c = 2.06 Joules per gram-degree Celsius<br />

The calculation needed, using words & symbols is:<br />

q = (mass) (Δt) (c)<br />

Why is this equation the way it is?<br />

Think about one gram going one degree. The ice needs 2.06 J for that. Now go the second degree.<br />

Another 2.06 J. Go the third degree and use another 2.06 J. So one gram going 10 degrees needs<br />

2.06 x 10 = 20.6 J. Now we have 72 grams, so gram #2 also needs 20.6, gram #3 needs 20.6 and so<br />

on until 72 grams.<br />

With the numbers in place, we have:<br />

q = (72.0 g) (10 °C) (2.06 J/g °C)<br />

So we calculate and get 1483.2 J. We won't bother to round off right now since there are four more<br />

calculations to go. Maybe you can see that we will have to do five calculations and then sum them all<br />

up.<br />

One warning before going on: three of the calculations will yield J as the unit on the answer and two<br />

will give kJ. When you add the five values together, you MUST have them all be the same unit.<br />

In the context of this problem, kJ is the preferred unit. You might want to think about what 1483.2 J is<br />

in kJ.<br />

Notes:<br />

The change of energy in ice, without going through a phase change, but actually just going through a change in<br />

temperature, can be calculated using the temperature change formula:<br />

Q (energy in Joules) = m(mass) x c(specific heat of ice) x T(change in temperature/ initial temp. -final temp.)<br />

135


Step Two: solid ice melts<br />

Now, we continue to add energy and the ice begins to<br />

melt.<br />

However, the temperature DOES NOT CHANGE. It<br />

remains at zero during the time the ice melts.<br />

Each mole of water will require a constant amount of<br />

energy to melt. That amount is named the molar heat of<br />

fusion and its symbol is ΔHf. The molar heat of fusion is<br />

the energy required to melt one mole of a substance at its<br />

normal melting point. One mole of solid water, one mole<br />

of solid benzene, one mole of solid lead. It does not<br />

matter. Each substance has its own value.<br />

During this time, the energy is being used to overcome water molecules' attraction for each other,<br />

destroying the three-dimensional structure of the ice.<br />

The unit for this is kJ/mol. Sometimes you see older references that use kcal/mol. The conversion<br />

between calories and Joules is 4.184 J = 1.000 cal.<br />

Sometimes you also see this number expressed "per gram" rather than "per mole." For example,<br />

water's molar heat of fusion is 6.02 kJ/mol. Expressed per gram, it is 334.16 J/g.<br />

Typically, the term "heat of fusion" is used with the "per gram" value.<br />

72.0 grams of solid water is 0.0 °C. It is going to melt AND stay at zero degrees. This is an important<br />

point. While the ice melts, its temperature will remain the same. We need to calculate the energy<br />

needed to do this.<br />

This summarizes the information needed:<br />

ΔHf = 6.02 kJ/mol<br />

The mass = 72.0 g<br />

The molar mass of H2O = 18.0 gram/mol<br />

The calculation needed, using words & symbols is:<br />

q = (moles of water) (ΔHf)<br />

We can rewrite the moles of water portion and make the equation like this:<br />

q = (grams water / molar mass of water) (ΔHf)<br />

Why is this equation the way it is?<br />

Think about one mole of ice. That amount of ice (one mole or 18.0 grams) needs 6.02 kilojoules of<br />

energy to melt. Each mole of ice needs 6.02 kilojoules. So the (grams water / molar mass of water) in<br />

the above equation calculates the amount of moles.<br />

With the numbers in place, we have:<br />

q = (72.0 g / 18.0 g mol¯1 ) (6.02 kJ / mol)<br />

So we calculate and get 24.08 kJ. We won't bother to round off right now since there are three more<br />

calculations to go. We're doing the second step now. When all five are done, we'll sum them all up.<br />

136


Step Three: liquid water rises in temperature<br />

Once the ice is totally melted, the temperature can now<br />

begin to rise again.<br />

It continues to go up until it reaches its normal boiling<br />

point of 100.0 °C.<br />

Since the temperature went from zero to 100, the Δt is<br />

100.<br />

Here is an important point: THE LIQUID HAS NOT<br />

BOILED YET.<br />

At the end of this step we have liquid water at 100 degrees. It has not turned to steam yet.<br />

Each gram of water requires a constant amount of energy to go up each degree Celsius. This amount<br />

of energy is called specific heat and has the symbol c. There will be a different value needed,<br />

depending on the substance being in the solid, liquid or gas phase.<br />

72.0 grams of liquid water is 0.0 °C. It is going to warm up to 100.0 °C, but at that temperature, the<br />

water WILL NOT BOIL. We need to calculate the energy needed to do this.<br />

This summarizes the information needed:<br />

Δt = 100.0 °C (100.0 °C – 0.0 °C)<br />

The mass = 72.0 g<br />

c = 4.184 Joules per gram-degree Celsius<br />

The calculation needed, using words & symbols is:<br />

q = (mass) (Δt) (c)<br />

Why is this equation the way it is?<br />

Think about one gram going one degree. The liquid water needs 4.184 J for that. Now go the second<br />

degree. Another 4.184 J. Go the third degree and use another 4.184 J. So one gram going 100<br />

degrees needs 4.184 x 100 = 418.4 J. Now we have 72 grams, so gram #2 also needs 418.4, gram<br />

#3 needs 418.4 and so on until 72 grams.<br />

With the numbers in place, we have:<br />

q = (72.0 g) (100.0 °C) (4.184 J/g °C)<br />

So we calculate and get 30124.8 J. We won't bother to round off right now since there are two more<br />

calculations to go. We will have to do five calculations and then sum them all up.<br />

Notes:<br />

The energy gained by the melting of ice, WITHOUT changing temperature, is still added to the total energy, but is<br />

calculated by the heat of fusion (Hf) because of the lack of a change of temperature. Once all the ice has melted<br />

into liquid water, the change in energy is once again calculated using the temperature change formula:<br />

Q (energy in Joules) = m(mass) x c(specific heat of water) x T(change in temperature/ initial temp. -final temp.)<br />

137


Step Four: liquid water boils<br />

Now, we continue to add energy and the water begins to<br />

boil.<br />

However, the temperature DOES NOT CHANGE. It<br />

remains at 100 during the time the water boils.<br />

Each mole of water will require a constant amount of<br />

energy to boil. That amount is named the molar heat of<br />

vaporization and its symbol is ΔH. The molar heat of<br />

vaporization is the energy required to boil one mole of a<br />

substance at its normal boiling point. One mole of liquid water, one mole of liquid benzene, one mole<br />

of liquid lead. It does not matter. Each substance has its own value.<br />

During this time, the energy is being used to overcome water molecules' attraction for each other,<br />

allowing them to move from close together (liquid) to quite far apart (the gas state).<br />

The unit for this is kJ/mol. Sometimes you see older references that use kcal/mol. The conversion<br />

between calories and Joules is 4.184 J = 1.000 cal.<br />

Typically, the term "heat of vaporization" is used with the "per gram" value.<br />

72.0 grams of liquid water is at 100.0 °C. It is going to boil AND stay at 100 degrees. This is an<br />

important point. While the water boils, its temperature will remain the same. We need to calculate the<br />

energy needed to do this.<br />

This summarizes the information needed:<br />

ΔH = 40.7 kJ/mol<br />

The mass = 72.0 g<br />

The molar mass of H2O = 18.0 gram/mol<br />

The calculation needed, using words & symbols is:<br />

q = (moles of water) (ΔH)<br />

We can rewrite the moles of water portion and make the equation like this:<br />

q = (grams water / molar mass of water) (ΔH)<br />

Why is this equation the way it is?<br />

Think about one mole of liquid water. That amount of water (one mole or 18.0 grams) needs 40.7<br />

kilojoules of energy to boil. Each mole of liquid water needs 40.7 kilojoules to boil. So the (grams<br />

water / molar mass of water) in the above equation calculates the amount of moles.<br />

With the numbers in place, we have:<br />

q = (72.0 g / 18.0 g mol¯1 ) (40.7 kJ / mol)<br />

So we calculate and get 162.8 kJ. We won't bother to round off right now since there is one more<br />

calculation to go. We're doing the fourth step now. When all five are done, we'll sum them all up.<br />

138


Step Five: steam rises in temperature<br />

Once the water is completely changed to steam, the<br />

temperature can now begin to rise again.<br />

It continues to go up until we stop adding energy. In this<br />

case, let the temperature rise to 120 °C.<br />

Since the temperature went from 100 °C to 120°C, the Δt<br />

is 20°C.<br />

Each gram of water requires a constant amount of energy<br />

to go up each degree Celsius. This amount of energy is called specific heat and has the symbol c.<br />

There will be a different value needed, depending on the substance being in the solid, liquid or gas<br />

phase.<br />

72.0 grams of steam is 100.0 °C. It is going to warm up to 120.0 °C. We need to calculate the energy<br />

needed to do this.<br />

This summarizes the information needed:<br />

Δt = 20 °C<br />

The mass = 72.0 g<br />

c = 2.02 Joules per gram-degree Celsius<br />

The calculation needed, using words & symbols is:<br />

q = (mass) (Δt) (c)<br />

Why is this equation the way it is?<br />

Think about one gram going one degree. The liquid water needs 2.02 J for that. Now go the second<br />

degree. Another 2.02 J. Go the third degree and use another 2.02 J. So one gram going 20 degress<br />

needs 2.02 x 20 = 44 J. Now we have 72 grams, so gram #2 also needs 44, gram #3 needs 44 and<br />

so on until 72 grams.<br />

I hope that helped.<br />

With the numbers in place, we have:<br />

q = (72.0 g) (20 °C) (2.02 J/g °C)<br />

So we calculate and get 2908.8 J. We won't bother to round off right now since we still need to sum<br />

up all five values.<br />

Notes:<br />

LIke with ice converting to water, the water boiling into steam takes energy, but that gain of energy is calculated by the<br />

heat of vaporization (Hv). That is added onto the total, along with the change in temperature of the steam, represented<br />

yet again by the equation featuring the change in temperature:<br />

Q (energy in Joules) = m(mass) x c(specific heat of steam) x T(change in temperature/ initial temp. -final temp.)<br />

139


The following table summarizes the five steps and their results. Each step number is a link back to<br />

the explanation of the calculation.<br />

Converting to kJ gives us this:<br />

1.4832 kJ<br />

24.08 kJ<br />

30.1248 kJ<br />

162.8 kJ<br />

2.9088 kJ<br />

Step q 72.0 g of H2O<br />

1 1483.2 J Δt = 10 (solid)<br />

2 24.08 kJ melting<br />

3 30124.8 J Δt = 100 (liquid)<br />

4 162.8 kJ boiling<br />

5 2908.8 J Δt = 20 (gas)<br />

Summing up gives 221.3968 kJ and proper significant digits gives us 221.4 kJ for the answer.<br />

Notice how all units were converted to kJ before continuing on. Joules is a perfectly fine unit; it's just<br />

that 221,396.8 J is an awkward number to work with. Usually Joules is used for values under 1000,<br />

otherwise kJ is used.<br />

By the way, on other sites you may see kj used for kilojoules. I've also seen Kj used. Both of these<br />

are wrong symbols. kJ is the only correct symbol.<br />

Enthalpy<br />

When a process occurs at constant pressure, the heat evolved (either released or absorbed) is equal<br />

to the change in enthalpy. Enthalpy (H) is the sum of the internal energy (U) and the product of<br />

pressure and volume (PV) given by the equation:<br />

H=U+PV<br />

When a process occurs at constant pressure, the heat evolved (either released or absorbed) is equal<br />

to the change in enthalpy. Enthalpy is a state function which depends entirely on the state<br />

functions T, P and U. Enthalpy is usually expressed as the change in enthalpy (ΔH) for a process<br />

between initial and final states:<br />

ΔH=ΔU+ΔPVΔ<br />

If temperature and pressure remain constant through the process and the work is limited to pressurevolume<br />

work, then the enthalpy change is given by the equation:<br />

ΔH=ΔU+PΔV<br />

Also at constant pressure the heat flow (q) for the process is equal to the change in enthalpy defined<br />

by the equation:<br />

ΔH=q<br />

By looking at whether q is exothermic or endothermic we can determine a relationship between ΔH<br />

and q. If the reaction absorbs heat it is endothermic meaning the reaction consumes heat from the<br />

surroundings so q>0 (positive). Therefore, at constant temperature and pressure, by the equation<br />

above, if q is positive then ΔH is also positive. And the same goes for if the reaction releases heat,<br />

140


then it is exothermic, meaning the system gives off heat to its surroundings, so q


The Learning Goal for this section is: Explain how various factors, such as concentration,<br />

temperature, and presence of a catalyst affect the rate of a chemical reaction.<br />

You are going to answer these 15 questions first in the order they are given to you. This will be a quiz grade. You are then going to explain the<br />

chemical concepts that are used in each question. You can do this in the order given or group them by concepts. You can use your book or information<br />

found on the internet but all information must be written in your own word. The font needs to be Arial 12. This is due on Monday April 24 by midnight in<br />

the drop box. This document should be a 6-page pdf.<br />

1. B 6. B 11. A<br />

2. C 7. B 12. D<br />

3. C 8. D 13. C<br />

4. D 9. A 14. A<br />

5. A 10. B 15. D<br />

1 This graph represents the change in energy for two laboratory trials of the same reaction.<br />

Which factor could explain the energy difference between the trials?<br />

A Heat was added to trial #2.<br />

B A catalyst was added to trial #2.<br />

C Trial #1 was stirred.<br />

D Trial #1 was cooled.<br />

*Catalysts speed up reaction times by making the process require less energy to actually undergo the<br />

reaction, a.k.a lowering the activation energy*<br />

2 Consider this balanced chemical equation:<br />

Which will increase the rate of the reaction?<br />

A increasing pressure on the reaction<br />

B decreasing concentration of the reactants<br />

C adding a catalyst to the reaction<br />

D decreasing the temperature of the reaction<br />

2H2O2 (aq) → 2H2O(l) + O2 (g)<br />

142


*Catalysts increase the rate of reaction without being used up during the reaction, and they reduce<br />

the activation energy for a reaction, making it so that reactions take less energy to occur. The other<br />

options just reduce the reaction rate by either lessening the amount of collisions between the particles<br />

of the reactants, or lessening the kinetic energy of the particles, which lessens the force between<br />

collisions.*<br />

3 For the reaction<br />

A + (aq) + B — (aq) → AB (s)<br />

increasing the temperature increases the rate of the reaction. Which is the best explanation for this<br />

happening?<br />

A The pressure increases, which in turn increases the production of products.<br />

B The concentration of reactants increases with an increase in temperature.<br />

C The average kinetic energy increases, so the likelihood of more effective collisions between ions<br />

increases.<br />

D Systems are more stable at high temperatures.<br />

* More collisions between particles occur with higher kinetic energy, and particles that have more<br />

kinetic energy also reach the activation energy requirement of a reaction more quickly, which<br />

increases the rate of the reaction. *<br />

4 Which statement explains why the speed of some reactions is increased when the surface area of<br />

one or all the reactants is increased?<br />

A increasing surface area changes the electronegativity of the reactant particles<br />

B increasing surface area changes the concentration of the reactant particles<br />

C increasing surface area changes the conductivity of reactant particles<br />

D increasing surface area enables more reactant particles to collide<br />

* When the Surface area of one or more reactants is increased, it allows for more particles to be<br />

undergoing collisions between the reactants, making the reaction go faster because more particles<br />

are colliding. *<br />

catalyst<br />

C6H6 + Br2 → C6H5Br + HBr<br />

5 Which of the following changes will cause an increase in the rate of the above reaction?<br />

A increasing the concentration of Br2<br />

B decreasing the concentration of C6H6<br />

C increasing the concentration of HBr<br />

D decreasing the temperature<br />

* By increasing the concentration of the reactant Br2, there would also be an increase in the collisions<br />

between particles. By increasing the rate of collisions, there would be an increase in the rate of the<br />

reaction. Decreasing the concentration or temperature of anything in the reaction would cause less<br />

collisions to occur, therefore slowing the reaction instead. *<br />

143


2CO + O2 → 2CO2<br />

6 If the above reaction takes place inside a sealed reaction chamber, then which of these procedures<br />

will cause a decrease in the rate of reaction?<br />

A raising the temperature of the reaction chamber<br />

B increasing the volume inside the reaction chamber<br />

C removing the CO2 as it is formed<br />

D adding more CO to the reaction chamber<br />

* By increasing the volume of the reaction chamber, the reactants occupy more space, making it so<br />

that the particles of the reactants don’t collide as often as they would’ve in that smaller space, so the<br />

reaction rate would decrease.*<br />

7 A catalyst can speed up the rate of a given chemical reaction by<br />

A increasing the equilibrium constant in favor of products.<br />

B lowering the activation energy required for the reaction to occur.<br />

C raising the temperature at which the reaction occurs.<br />

D increasing the pressure of reactants, thus favoring products.<br />

*Catalysts lower the activation energy (minimum energy for a reaction to occur) of a reaction,<br />

therefore making a reaction require less energy to actually occur. They not only lower the activation<br />

energy, but this also gives reactants more energy to form products within a given time, which<br />

increases the rate of reaction. *<br />

8 Which reaction diagram shows the effect of using the appropriate catalyst in a chemical reaction?<br />

A<br />

C<br />

B<br />

D<br />

*A catalyst lowers the energy required for the reaction to occur and the reaction would not reach the<br />

energy levels that the same reaction without the catalyst would reach, as demonstrated by the graph<br />

without the catalyst vs. with the catalyst. *<br />

144


9 H2O2, hydrogen peroxide, naturally breaks down into H2O and O2 over time. MnO2, manganese<br />

dioxide, can be used to lower the energy of activation needed for this reaction to take place and, thus,<br />

increase the rate of reaction. What type of substance is MnO2?<br />

A a catalyst<br />

B an enhancer<br />

C an inhibitor<br />

D a reactant<br />

*catalysts lower the energy required for a reaction to take place, and MnO2 lowers the energy for<br />

H2O2 to react and decompose. If manganese is the substance that lowers the activation energy, then<br />

manganese is a catalyst. If manganese were a reactant it would not lower the activation energy of the<br />

reaction, and possibly even make the reaction require more energy to occur instead of less energy<br />

being needed. *<br />

10 When a reaction is at equilibrium and more reactant is added, which of the following changes is<br />

the immediate result?<br />

A The reverse reaction rate remains the same.<br />

B The forward reaction rate increases.<br />

C The reverse reaction rate decreases.<br />

D The forward reaction rate remains the same.<br />

* A reaction being at equilibrium means that the forward reaction rate (the initial reactants) and<br />

reverse reaction rate (the initial products) have reached an equal rate of conversion between each<br />

other. By adding more reactants, the forward reaction would have to go through more in order to<br />

attain equilibrium once again. The other choices do not display equilibrium, because the reaction<br />

rates staying the same would mean that equilibrium would not be achieved in the end, and in nature,<br />

equilibrium is supposed to be achieved. *<br />

11 In which of the following reactions involving gases would the forward reaction be favored by an<br />

increase in pressure?<br />

A A + B ⇄AB<br />

B A + B ⇄ C + D<br />

C 2A + B ⇄ C + 2D<br />

D AC ⇄ A + C<br />

* By increasing the pressure in a reaction, the point of equilibrium would be shifted towards the side<br />

that had fewer molecules. With the two molecules A and b reacting and creating the product AB, an<br />

increase in pressure would favor the forward reaction, and the point of equilibrium would try to move<br />

to counteract that change. Pretty much, the point of equilibrium will move so that the pressure will be<br />

reduced to its initial state. *<br />

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12 Which action will drive the reaction to the right?<br />

A heating the equilibrium mixture<br />

B adding water to the system<br />

C decreasing the oxygen concentration<br />

D increasing the system’s pressure<br />

4HCl(g) + O2(g) ⇄ 2H2O(l) + 2Cl2(g) + 113 kJ<br />

* Increasing the pressure on this reaction would drive the reaction to the right, because when the<br />

pressure is increased in a reaction, the point of equilibrium is shifted towards the side with less<br />

molecules. In this reaction, the right side has less molecules, and so the system will try to achieve<br />

equilibrium in order to reduce the pressure to its original amount. In order to do this, it’s shifted from<br />

left to right*<br />

NO2(g) + CO(g) ⇄ NO(g) + CO2(g)<br />

13 The reaction shown above occurs inside a closed flask. What action will shift the reaction to the<br />

left?<br />

A pumping CO gas into the closed flask<br />

B raising the total pressure inside the flask<br />

C increasing the NO concentration in the flask<br />

D venting some CO2 gas from the flask<br />

* In order to shift the reaction to the left, increasing the concentration of NO would be the most viable<br />

method. NO is a product, and by increasing its concentration, it will collide more with CO2, causing<br />

the reaction to shift to the left. If you were to pump in more CO the reaction rate would only shift to the<br />

right because of the increased amount of collisions on the right side, and venting out CO2 would only<br />

make the reaction try to reach equilibrium from the left to the right. Raising the total pressure would<br />

barely do anything at all, because the number of molecules on both sides wouldn’t change at all, so<br />

the equilibrium wouldn’t move in any way to try to reduce the pressure, meaning that the reaction<br />

would not shift at all.<br />

NH4Cl(s) + heat ⇄ NH3(g) + HCl(g)<br />

14 What kind of change will shift the reaction above to the right to form more products?<br />

A a decrease in total pressure<br />

B an increase in the concentration of HCl<br />

C an increase in the pressure of NH3<br />

D a decrease in temperature<br />

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* When a decrease in pressure happens, only the concentration of gasses is affected. The gases are<br />

on the right of the equation, and by decreasing the total pressure of the reaction, this would lead to<br />

the reaction trying to achieve equilibrium by shifting from the left to the right. The reaction was<br />

originally shifted toward the left because of there being more products. Increasing the concentration<br />

of HCl would shift the reaction to the left because of the increased amount of collisions between HCl<br />

and NH3. If the pressure of NH3 were increased, this would lead to an increased concentration of<br />

NH3, which would also lead to more collisions between NH3 and HCl, which again would shift the<br />

reaction to the left. If the temperature were decreased, the reaction would be shifted towards heat,<br />

which is on the left side.*<br />

15 In a sealed bottle that is half full of water, equilibrium will be attained when water molecules<br />

A cease to evaporate.<br />

B begin to condense.<br />

C are equal in number for both the liquid and the gas phase.<br />

D evaporate and condense at equal rates.<br />

*Equilibrium of a reaction is the point at which the conversion between the two substances (in this<br />

case, phases) is equal, keeping both substances converting between each other at equal amounts.<br />

The reactants (water) and products (vapor) must be an equal rate of conversion in order to achieve<br />

equilibrium, which is only demonstrated by water molecules evaporating and condensing at equal<br />

rates. If water molecules were to cease to evaporate, this would clearly not be equilibrium, because<br />

there would be no conversions to vapor at all anymore. The amounts of molecules in the liquid and<br />

gas phase being equal doesn’t matter either, because that does not demonstrate the reaction rate<br />

between the two being equal. If water were only “beginning to condense” then the reaction at that<br />

point would be clearly one sided, seeing as the rates of condensation and evaporation are clearly not<br />

equal if condensation had only begun. *<br />

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Unit 8<br />

Chapter 19 Acid and Bases<br />

The student will learn what are the different ways chemists<br />

define aids and bases, what the pH of a solution means and<br />

how chemist use acid-base reactions.<br />

Relate acidity and basicity to hydronium and hydroxyl ion concentration and<br />

pH.<br />

<br />

<br />

<br />

Students will be able to use a pH scale to identify substances as acids or bases.<br />

Students will be able to use various equipment (probeware, universal pH, etc.) to<br />

identify the pH of substances.<br />

Students will be able to calculate H3O+ and OH- concentration of various<br />

substances.<br />

pH scale<br />

Hydronium ion<br />

Arrhenius acid/base<br />

Lewis acid/base<br />

Bronsted-Lowry acid/base<br />

Strong acid/base<br />

Weak acid/base<br />

Neutralization reaction<br />

Titration<br />

Chapter 20 Oxidation-Reduction Reactions<br />

The student will learn what happens during oxidation and<br />

reduction and how to balance redox equations.<br />

Describe oxidation-reduction reactions in living and non-living systems.<br />

<br />

<br />

<br />

Students will be able to compare and contrast redox reactions.<br />

Students will be able to assign oxidation numbers to redox reactions.<br />

Students will be able to write half reactions<br />

Oxidation<br />

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Reduction<br />

Oxidation reduction reaction<br />

Oxidation number<br />

Half reaction<br />

Electrochemical process<br />

Battery<br />

Cathode<br />

Anode<br />

Electrolysis<br />

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The Learning Goal for this section is: Relate acidity and basicity to hydronium and hydroxyl ion concentration and pH<br />

Acids and Bases<br />

The Observable Properties of Acids and Bases<br />

The words acid and alkaline (an older word for base) are derived from direct sensory experience.<br />

Acid Property #1:<br />

The word acid comes from the Latin word acere, which means "sour." All acids taste sour. Well<br />

known from ancient times were vinegar, sour milk and lemon juice. Aspirin (scientific name:<br />

acetylsalicylic acid) tastes sour if you don't swallow it fast enough. Other languages derive their word<br />

for acid from the meaning of sour. So, in France, we have acide. In Germany, we have säure from<br />

saure and in Russia, kislota from kisly.<br />

Base Property #1:<br />

The word "base" has a more complex history (see below) and its name is not related to taste. All<br />

bases taste bitter. For example, mustard is a base. It tastes bitter. Many medicines, because they are<br />

bases, taste bitter. This is the reason cough syrups are advertised as having a "great grape taste."<br />

The taste is added in order to cover the bitterness of the active ingredient in cough syrup.<br />

Acid Property #2:<br />

Acids make a blue vegetable dye called litmus turn red.<br />

Base Property #2:<br />

Bases are substances which will restore the original blue color of litmus after having been reddened<br />

by an acid.<br />

Acid Property #3:<br />

Acids destroy the chemical properties of bases.<br />

Base Property #3:<br />

Bases destroy the chemical properties of acids.<br />

Neutralization is the name for this type of reaction.<br />

Acid Property #4:<br />

Acids conduct an electric current.<br />

Base Property #4:<br />

Bases conduct an electric current.<br />

This is a common property shared with salts. Acids, bases and salts are grouped together into a<br />

category called electrolytes, meaning that a water solution of the given substance will conduct an<br />

electric current.<br />

Non-electrolyte solutions cannot conduct a current. The most common example of this is sugar<br />

dissolved in water.<br />

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So far, the properties have an obvious relationship: taste, color change, mutual destruction, and<br />

response to electric current. This last property is related, but in a less obvious way. The property<br />

below identifies a unique chemical reaction that acids and bases engage in.<br />

Acid Property #5:<br />

Upon chemically reacting with an active metal, acids will evolve hydrogen gas (H2). The key word, of<br />

course, is active. Some metals, like gold, silver or platinum, are rather unreactive and it takes rather<br />

extreme conditions to get these "unreactive" metals to react. Not so with the metals in this property.<br />

They include the alkali metals (Group I, Li to Rb), the alkaline earth metals (Group II, Be to Ra), as<br />

well as zinc and aluminum. Just bring the acid and the metal together at anything close to room<br />

temperature and you get a reaction. Here's a sample reaction:<br />

Zn + 2 HCl(aq) ---> ZnCl2 + H2<br />

Another common acid reaction some sources mention is that acids react with carbonates (and<br />

bicarbonates) to give carbon dioxide gas:<br />

HCl + NaCO3 ---> CO2 + H2O + NaCl<br />

Base Property #5:<br />

Bases feel slippery, sometimes people say soapy. This is because they dissolve the fatty acids and<br />

oils from your skin and this cuts down on the friction between your fingers as you rub them together.<br />

In essence, the base is making soap out of you. Yes, bases are involved in the production of soap! In<br />

the early years of soap making, the soaps were very harsh on the skin and clothes due to the high<br />

base content. Even today, people with very sensitive skin must sometimes use a non-soap-based<br />

product for bathing.<br />

It was not until more modern times that the chemical nature (as opposed to observable properties) of<br />

acids and bases began to be explored. That leads to this property that is not directly observable by<br />

the senses.<br />

Acid Property #6:<br />

Acids produce hydrogen ion (H + ) in solution. A more correct formula for what is produced is that of the<br />

hydronium ion, H3O + . Both formulas are used interchangeably.<br />

Acid base theories: Svante Arrhenius<br />

I. Introduction<br />

The basic idea is that certain substances remain ionized in solution all the time. Today, everyone<br />

accepts this without question, but it was the subject of much dissention and disagreement in 1884,<br />

when a twenty-five-year-old Arrhenius presented and defended his dissertation.<br />

II. The Acid Base Theory<br />

Acid - any substance which delivers hydrogen ion (H + ) to the solution.<br />

Base - any substance which delivers hydroxide ion (OH¯) to the solution.<br />

Here is a generic acid dissociating, according to Arrhenius:<br />

HA ---> H + + A¯<br />

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This would be a generic base:<br />

XOH ---> X + + OH¯<br />

When acids and bases react according to this theory, they neutralize each other, forming water and a<br />

salt:<br />

HA + XOH ---> H2O + XA<br />

Keeping in mind that the acid, the base and the salt all ionize, we can write this:<br />

Finally, we can drop all spectator ions, to get this:<br />

H + + A¯ + X + + OH¯ ---> H2O + X + + A¯<br />

H + + OH¯ ---> H2O<br />

These ideas covered all of the known acids at the time (the usual suspects like hydrochloric acid,<br />

acetic acid, and so on) and most of the bases (sodium hydroxide, potassium hydroxide, calcium<br />

hydroxide and so on). HOWEVER, and it is a big however, the theory did not explain why ammonia<br />

(NH3) was a base. There are other problems with the theory also.<br />

III. Problems with Arrhenius' Theory<br />

1. The solvent has no role to play in Arrhenius' theory. An acid is expected to be an acid in any<br />

solvent. This was found to not be the case. For example, HCl is an acid in water, behaving in<br />

the manner Arrhenius expected. However, if HCl is dissolved in benzene, there is no<br />

dissociation, the HCl remaining as un-dissociated molecules. The nature of the solvent plays a<br />

critical role in acid-base properties of substances.<br />

2. All salts in Arrhenius' theory should produce solutions that are neither acidic or basic. This is<br />

not the case. If equal amounts of HCl and ammonia react, the solution is slightly acidic. If equal<br />

amounts of acetic acid and sodium hydroxide are reacted, the resulting solution is basic.<br />

Arrhenius had no explanation for this.<br />

3. The need for hydroxide as the base led Arrhenius to propose the formula NH4OH as the<br />

formula for ammonia in water. This led to the misconception that NH4OH is the actual base,<br />

not NH3.<br />

In fact, by 1896, several years before Arrhenius announced his theory, it had been recognized that<br />

characteristic base properties where just as evident in such solvents as aniline, where no hydroxide<br />

ions were possible.<br />

4. H + , a bare proton, does not exist for very long in water. The proton affinity of H2O is about 799<br />

kJ/mol. Consequently, this reaction:<br />

H2O + H + ---> H3O +<br />

happens to a very great degree. The "concentration" of free protons in water has been estimated to<br />

be 10¯130 M. A rather preposterous value, indeed.<br />

The Arrhenius theory of acids and bases will be fully supplanted by the theory proposed<br />

independently by Johannes and Thomas Lowry in 1923.<br />

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The acid base theory of Brønsted and Lowry<br />

I. Introduction<br />

In 1923, within several months of each other, Johannes Nicolaus Brønsted (Denmark) and Thomas<br />

Martin Lowry (England) published essentially the same theory about how acids and bases behave.<br />

Since they came to their conclusions independently of each other, both names have been used for<br />

the theory name.<br />

II. The Acid Base Theory<br />

Using the words of Brønsted:<br />

". . . acids and bases are substances that are capable of splitting off or taking up hydrogen ions,<br />

respectively."<br />

Or an acid-base reaction consists of the transfer of a proton from an acid to a base. KEEP THIS<br />

THOUGHT IN MIND!!<br />

Here is a more recent way to say the same thing:<br />

An acid is a substance from which a proton can be removed.<br />

A base is a substance that can remove a proton from an acid.<br />

Remember: proton, hydrogen ion and H + all mean the same thing<br />

Very common in the chemistry world is this definition set:<br />

An acid is a "proton donor."<br />

A base is a "proton acceptor."<br />

In an acid, the hydrogen ion is bonded to the rest of the molecule. It takes energy (sometimes a little,<br />

sometimes a lot) to break that bond. So the acid molecule does not "give" or "donate" the proton, it<br />

has it taken away. In the same sense, you do not donate your wallet to the pickpocket, you have it<br />

removed from you.<br />

The base is a molecule with a built-in "drive" to collect protons. As soon as the base approaches the<br />

acid, it will (if it is strong enough) rip the proton off the acid molecule and add it to itself.<br />

Now this is where all the fun stuff comes in that you get to learn. You see, some bases are stronger<br />

than others, meaning some have a large "desire" for protons, while other bases have a weaker drive.<br />

It's the same way with acids, some have very weak bonds and the proton is easy to pick off, while<br />

other acids have stronger bonds, making it harder to "get the proton."<br />

One important contribution coming from Lowry has to do with the state of the hydrogen ion in solution.<br />

In Brønsted's announcement of the theory, he used H + . Lowry, in his paper (actually a long letter to<br />

the editor) used the H3O + that is commonly used today.<br />

III. Sample Equations written in the Brønsted-Lowry Style<br />

A. Reactions that proceed to a large extent:<br />

153


HCl + H2O ⇌ H3O + + Cl¯<br />

HCl - this is an acid, because it has a proton available to be transferred.<br />

H2O - this is a base, since it gets the proton that the acid lost.<br />

Now, here comes an interesting idea:<br />

H3O + - this is an acid, because it can give a proton.<br />

Cl¯ - this is a base, since it has the capacity to receive a proton.<br />

Notice that each pair (HCl and Cl¯ as well as H2O and H3O + differ by one proton (symbol = H + ). These<br />

pairs are called conjugate pairs.<br />

HNO3 + H2O ⇌ H3O + + NO3¯<br />

The acids are HNO3 and H3O + and the bases are H2O and NO3¯.<br />

Remember that an acid-base reaction is a competition between two bases (think about it!) for a<br />

proton. If the stronger of the two acids and the stronger of the two bases are reactants (appear on the<br />

left side of the equation), the reaction is said to proceed to a large extent.<br />

Here are some more conjugate acid-base pairs to look for:<br />

H2O and OH¯<br />

HCO3¯ and CO3 2¯<br />

H2PO4¯ and HPO4 2¯<br />

HSO4¯ and SO4 2¯<br />

NH4 + and NH3<br />

CH3NH3 + and CH3NH2<br />

HC2H3O2 and C2H3O2¯<br />

B. Reactions that proceed to a small extent:<br />

If the weaker of the two acids and the weaker of the two bases are reactants (appear on the left side<br />

of the equation), the reaction is said to proceed to only a small extent:<br />

HC2H3O2 + H2O ⇌ H3O + + C2H3O2¯<br />

NH3 + H2O ⇌ NH4 + + OH¯<br />

Identify the conjugate acid base pairs in each reaction.<br />

HC 2H 3O 2 and C 2H 3O 2¯<br />

is one conjugate pair.<br />

H 2O and H 3O + is the other.<br />

NH 3 and NH 4<br />

+<br />

is one pair.<br />

H 2O and OH¯ is the other.<br />

Notice that H 2O in the first equation is acting as a base and in the second equation is acting as an acid.<br />

154


IV. Problems with the Theory<br />

This theory works very nicely in all protic solvents (water, ammonia, acetic acid, etc.), but fails to<br />

explain acid base behavior in aprotic solvents such as benzene and dioxane. That job will be left for a<br />

more general theory, such as the Lewis Theory of Acids and Bases.<br />

The Lewis theory of acids and bases<br />

I. Introduction<br />

Lewis gives his definition of an acid and a base:<br />

"We are inclined to think of substances as possessing acid or basic properties, without having a<br />

particular solvent in mind. It seems to me that with complete generality we may say that a basic<br />

substance is one which has a lone pair of electrons which may be used to complete the stable group<br />

of another atom, and that an acid is one which can employ a lone pair from another molecule in<br />

completing the stable group of one of its own atoms."<br />

"In other words, the basic substance furnishes a pair of electrons for a chemical bond, the acid<br />

substance accepts such a pair."<br />

It is important to make two points here:<br />

1. NO hydrogen ion need be involved.<br />

2. NO solvent need be involved.<br />

The Lewis theory of acids and bases is more general than the "one sided" nature of the Bronsted-<br />

Lowry theory. Keep in mind that Bronsted-Lowry, which defines an acid as a proton donor and a base<br />

as a proton acceptor, REQUIRES the presence of a solvent, specifically a protic solvent, of which<br />

water is the usual example. Since almost all chemistry is done in water, the fact that this limits the<br />

Bronsted-Lowry definition is of little practical consequence.<br />

The Lewis definitions of acid and base do not have the constraints that the Bronsted-Lowry theory<br />

does and, as we shall see, many more reactions were seen to be acid base in nature using the Lewis<br />

definition than when using the Bronsted-Lowry definitions.<br />

II. The Acid Base Theory<br />

The modern way to define a Lewis acid and base is a bit more concise than above:<br />

Acid: an electron acceptor.<br />

Base: an electron donor.<br />

A "Lewis acid" is any atom, ion, or molecule which can accept electrons and a "Lewis base" is any<br />

atom, ion, or molecule capable of donating electrons. However, a warning: many textbooks will say<br />

"electron pair" where I have only written "electron." The truth is that it sometimes is an electron pair<br />

and sometimes it is not.<br />

It turns out that it may be more accurate to say that "Lewis acids" are substances which are electrondeficient<br />

(or low electron density) and "Lewis bases" are substances which are electron-rich (or high<br />

electron density).<br />

155


Several categories of substances can be considered Lewis acids:<br />

1. positive ions<br />

2. having less than a full octet in the valence shell<br />

3. polar double bonds (one end)<br />

4. expandable valence shells<br />

Several categories of substances can be considered Lewis bases:<br />

1. negative ions<br />

2. one of more unshared pairs in the valence shell<br />

3. polar double bonds (the other end)<br />

4. the presence of a double bond<br />

Sören Sörenson and the pH scale<br />

I. Short Historical Introduction<br />

In the late 1880's, Svante Arrhenius proposed that acids were substances that delivered hydrogen ion<br />

to the solution. He has also pointed out that the law of mass action could be applied to ionic<br />

reactions, such as an acid dissociating into hydrogen ion and a negatively charged anion.<br />

This idea was followed up by Wilhelm Ostwald, who calculated the dissociation constants (the<br />

modern symbol is Ka) of many weak acids. Ostwald also showed that the size of the constant is a<br />

measure of an acid's strength.<br />

By 1894, the dissociation constant of water (today called Kw) was measured to the modern value of<br />

1 x 10¯14 .<br />

In 1904, H. Friedenthal recommended that the hydrogen ion concentration be used to characterize<br />

solutions. He also pointed out that alkaline (modern word = basic) solutions could also be<br />

characterized this way since the hydroxyl concentration was always 1 x 10¯14 ÷ the hydrogen ion<br />

concentration. Many consider this to be the real introduction of the pH scale.<br />

III. The Introduction of pH<br />

Sörenson defined pH as the negative logarithm of the hydrogen ion concentration.<br />

pH = - log [H + ]<br />

Remember that sometimes H3O + is written, so<br />

pH = - log [H3O + ]<br />

means the same thing.<br />

So let's try a simple problem: The [H + ] in a solution is measured to be 0.010 M. What is the pH?<br />

The solution is pretty straightforward. Plug the [H + ] into the pH definition:<br />

pH = - log 0.010<br />

An alternate way to write this is:<br />

pH = - log 10¯2<br />

Since the log of 10¯2 is -2, we have:<br />

pH = - (- 2)<br />

Which, of course, is 2.<br />

156


Let's discuss significant figures and pH.<br />

Another sample problem: Calculate the pH of a solution in which the [H3O + ] is 1.20 x 10¯3 M.<br />

For the solution, we have:<br />

pH = - log 1.20 x 10¯3<br />

This problem can be done very easily using your calculator. However, be warned about putting<br />

numbers into the calculator.<br />

So you enter (-), log, 1.20, X10 n , (-), 3, enter.<br />

The answer, to the proper number of significant digits is: 2.921.<br />

III. Significant Figures in pH<br />

Here is the example problem: Calculate the pH of a solution where the [H + ] is 0.00100 M. (This could<br />

also be a pOH problem. The point being made is the same.)<br />

OK, you say, that's pretty easy, the answer is 3. After all, 0.00100 is 10¯3 and the negative log of 10¯3<br />

is 3.<br />

You would be graded wrong!! Why? Because the pH is not written to reflect the number of significant<br />

figures in the concentration.<br />

Notice that there are three sig figs in 0.00100. (Hopefully you remember significant figures, since you<br />

probably studied them months ago before getting to acid base stuff. THEY ARE STILL IMPORTANT!)<br />

So, our pH value should also reflect three significant figures.<br />

However, there is a special rule to remember with pH (and pOH) values. The whole number portion<br />

DOES NOT COUNT when figuring out how many digits to write down.<br />

Let's phrase that another way: in a pH (and a pOH), the only place where significant figures are<br />

contained is in the decimal portion.<br />

So, the correct answer to the above problem is 3.000. Three sig figs and they are all in the decimal<br />

portion, NOT (I repeat NOT) in the whole number portion.<br />

Practice Problems<br />

Convert each hydrogen ion concentration into a pH. Identify each as an acidic pH or a basic pH.<br />

1. 0.0015 -> -log(0.0015) = 2.8239 = 2.82 pH = Acid<br />

2. 5.0 x 10¯9 -> -log (5.0 x 10^-9) = 8.301029996 = 8.30 pH = Base<br />

3. 1.0 -> -log(1) = 0.00 pH = STRONG Acid<br />

4. 3.27 x 10¯4 -> -log(3.27 x 10^-4) = 3.485452247 = 3.485 pH = Acid<br />

5. 1.00 x 10¯12 -> -log(1.00 x 10^-12) = 12.000 pH = Base<br />

6. 0.00010 -> -log(0.00010) = 4.00 pH = Acid<br />

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1. 2.82<br />

2. 8.30<br />

3. 0.00<br />

4. 3.485<br />

5. 12.000<br />

6. 4.00<br />

Sörenson also just mentions the reverse direction. That is, suppose you know the pH and you want to<br />

get to the hydrogen ion concentration ([H + ])?<br />

Here is the equation for that:<br />

[H + ] = 10¯pH<br />

That's right, ten to the minus pH gets you back to the [H + ] (called the hydrogen ion concentration).<br />

This is actually pretty easy to do with the calculator. Here's the sample problem: calculate the [H + ]<br />

from a pH of 2.45.<br />

This problem can be done very easily using your calculator. However, be warned about putting<br />

numbers into the calculator.<br />

So you enter 2nd, 10 x , (-), 2.45, enter.<br />

The answer, to the proper number of significant digits is: .00355.<br />

The pH of an acidic pond is 5. What is the hydrogen ion concentration (moles per liter)?<br />

The answer is:<br />

pH = -log (hydrogen ion concentration)<br />

The answer was .00001. Thus, 5 = -log (.00001).<br />

We'll take the formula that you started with (pH = -log([H+])) and work to the answer (solve for [H+]).<br />

pH = - log ([H+]) Given.<br />

pH = log ([H+] (-1) ) Since logarithms are like exponents, when you multiply a log by<br />

something, you can just move it to the inside of log as an exponent.<br />

10 pH = 10 log ([H+] (-1)) Take each side to tenth power.<br />

10 pH = [H+] (-1) Since "log" is just another notation for "log base 10", when you<br />

raise a log to the tenth power, the log cancels out.<br />

[H+] = 10 (-pH)<br />

Take the reciprocal of both sides.<br />

That is the general form. To answer the specific question,<br />

5 = - log ([H+])<br />

5 = log ([H+] (-1) )<br />

10 5 = [H+] (-1)<br />

10 (-5) = [H+]<br />

[H+]<br />

= .00001 mol/L<br />

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On your calculator you would input 10, ^, (-), 5 and you would get 0.00001.<br />

This is also the way to find the amount of OH + that are present in a base.<br />

To find the pH: -log(concentration)<br />

To find the concentration: 10 -pH<br />

Define these terms:<br />

pH scale<br />

The pH scale is on a scale of 0-14, 7 being neutral, above 7 being basic, and below 7 being acidic. The closer the pH of a<br />

substance is to either 0/14, the stronger the acid/base is. Acids are comprised of substances with a Hydrogen ion (H+), and<br />

bases comprised of Hydroxide ions (OH-). The pH of a substance can be tested using litmus paper, and bases turn red litmus<br />

blue, and vice versa for acids. pH (or pOH) is also calculated by the -log of the concentration of Hydrogen (or Hydroxide) ions.<br />

Hydronium ion<br />

A Hydronium ion is H3O,<br />

Arrhenius acid/base<br />

Acid- any substance which deliver hydrogen ions to the solution<br />

Base- any substance which delivers a hydroxide ion to the solution<br />

This theory was very limited, becuase if a compound had a hydroxide ion or hydrogen ion, but did not release into a solution, it<br />

would not be considered an acid/base. This theory assumed that acid/base neutralize each other, then formed a water and salt.<br />

Lewis acid/base<br />

Lewis acids/bases differ from the other theories due to the fact that they don't require Hydrogen ions, nor a solvent. In basic terms,<br />

A Lewis acid is a substance that recieves/accepts electrons and a base is a substance that gives off electrons. Due to this, acids<br />

and bases are more generalized, and positive ions would generally be considered acids and negative ions bases. This theory<br />

gives a more broad category of acids and bases than the other theories.<br />

Bronsted-Lowry acid/base<br />

Acid- a substance from which a proton can be removed (proton donor)<br />

Base- a substance that can remove a proton from an acid (proton acceptor)<br />

Strong acid/base<br />

A strong acid or base is constituted of a base (with a high pH) / acid (with a low pH) that readily gives away its hydrogen atoms.<br />

These mostly consist of ionic compounds, seeing as they are more likely to give away a hydrogen when reacting with another<br />

compound, which makes it a stronger base/acid.<br />

Weak acid/base<br />

A weak acid or base is constituted of a base (with a pH closer to 7) / acid (with a low pH) that readily gives away its hydrogen atoms.<br />

These mostly consist of ionic compounds, seeing as they are more likely to give away a hydrogen when reacting with another<br />

compound, which makes it a stronger base/acid.<br />

Neutralization reaction<br />

A neutralization reaction is when an acid destroys the chemical properties of a base, as well as the base destroying the chemical<br />

properties of the acid at the same time, therefore neutralizing each other.<br />

Titration<br />

Titration is a process used to determine the concentration of an unkown substance, using a substance with a known<br />

concentration.<br />

159


Redox Reactions Problems<br />

1. Determine the oxidation number of each element in the following compounds.<br />

Rules:<br />

A. Pure elements have an oxidation number of 0<br />

B. If the compound is an ionic compound, the oxidation number for each element is the ion’s<br />

charge<br />

C. The oxidation number of hydrogen in a compound is +1<br />

D. The oxidation number of oxygen in most compounds is –2<br />

(peroxides are the exception; in peroxides oxygen has an oxidation number of –1)<br />

E. The sum of the oxidation numbers in a compound is zero.<br />

F. The sum of the oxidation numbers in a polyatomic ion is equal to the ion charge.<br />

A SnCl4 Rule 2 Sn +4 Cl -1<br />

B Ca3P2 Rule 2 Ca +2 P -3<br />

C SnO Rules 4, 5 Sn +2 O -2<br />

D Ag2S Rule 2 Ag +1 S -2<br />

E HI Rule 3, 5 H +1 I -1<br />

F N2H4 Rule 3, 5 N -2 H +1<br />

G Al2O3 Rule 4, 5 Al +3 O -2<br />

H S8 Rule 1 S 0<br />

I HNO2 Rules 3, 4, 5 H N O<br />

J O2 Rule 1 O<br />

K H3O + Rules 3, 4, 6 H +1 O -2<br />

L ClO3 - Rules 4, 6 Cl +5 O -2<br />

M<br />

S2O32-<br />

Rules 4, 6 S +2 O -2<br />

+1 +3 -2<br />

0<br />

N KMnO4 Rules 4, 5, 6 K +1 Mn +7 O -2<br />

O (NH4)2SO4 Rules 4, 5, 6 N H S O<br />

2. Determine the oxidation number of carbon in each of the following compounds:<br />

a. methane, CH4 b. formaldehyde, CH2O<br />

C = -4 * 1 = -4<br />

H= +1 * 4 = +4 = 0 C = 0 * 1 = 0<br />

H = +1*2 = +2<br />

O = -2*1 = -2<br />

c. carbon monoxide, CO d. carbon dioxide, CO2<br />

C= +2<br />

O= -2 = 0 C = +4*1 = +4<br />

O = -2 *2 = -4 =0<br />

-3 +1 +6 -2<br />

= 0<br />

160


Reference Tables for Physical Setting/CHEMISTRY<br />

Table A<br />

Standard Temperature and Pressure<br />

Name Value Unit<br />

Standard Pressure 101.3 kPa kilopascal<br />

1 atm atmosphere<br />

Standard Temperature 273 K kelvin<br />

0°C degree Celsius<br />

Table D<br />

Selected Units<br />

Symbol Name Quantity<br />

m meter length<br />

g gram mass<br />

Pa pascal pressure<br />

K kelvin temperature<br />

Table B<br />

Physical Constants for Water<br />

mol<br />

J<br />

mole<br />

joule<br />

amount of<br />

substance<br />

energy, work,<br />

quantity of heat<br />

Heat of Fusion<br />

Heat of Vaporization<br />

Specific Heat Capacity of H 2<br />

O()<br />

Specific Heat Capacity of H 2<br />

O(s)<br />

Specific Heat Capacity of H 2<br />

O(g)<br />

Table C<br />

Selected Prefixes<br />

Factor Prefix Symbol<br />

10 3 kilo- k<br />

334 J/g<br />

2260 J/g<br />

4.18 J/g•K<br />

2.10 J/g•K<br />

2.01 J/g•K<br />

s second time<br />

min minute time<br />

h hour time<br />

d day time<br />

y year time<br />

L liter volume<br />

ppm parts per million concentration<br />

M<br />

molarity<br />

solution<br />

concentration<br />

u atomic mass unit atomic mass<br />

10 –1 deci- d<br />

10 –2 centi- c<br />

10 –3 milli- m<br />

10 –6 micro- μ<br />

10 –9 nano- n<br />

10 –12 pico- p<br />

R1


Table E<br />

Selected Polyatomic Ions<br />

Formula Name Formula Name<br />

H 3<br />

O +<br />

hydronium<br />

CrO 4<br />

2–<br />

chromate<br />

Hg 2<br />

2+<br />

mercury(I)<br />

Cr 2<br />

O 7<br />

2–<br />

dichromate<br />

NH 4<br />

+<br />

C 2<br />

H 3<br />

O<br />

–<br />

2 –}<br />

CH 3<br />

COO<br />

CN –<br />

CO 3<br />

2–<br />

HCO<br />

–<br />

3<br />

C 2<br />

O<br />

2–<br />

4<br />

ClO –<br />

ammonium<br />

acetate<br />

cyanide<br />

carbonate<br />

hydrogen<br />

carbonate<br />

oxalate<br />

hypochlorite<br />

MnO 4<br />

–<br />

NO<br />

–<br />

2<br />

NO<br />

–<br />

3<br />

O<br />

2–<br />

2<br />

OH –<br />

PO 4<br />

3–<br />

SCN –<br />

SO 3<br />

2–<br />

permanganate<br />

nitrite<br />

nitrate<br />

peroxide<br />

hydroxide<br />

phosphate<br />

thiocyanate<br />

sulfite<br />

ClO 2<br />

–<br />

chlorite<br />

SO 4<br />

2–<br />

sulfate<br />

ClO 3<br />

–<br />

chlorate<br />

HSO 4<br />

–<br />

hydrogen sulfate<br />

ClO 4<br />

–<br />

perchlorate<br />

S 2<br />

O 3<br />

2–<br />

thiosulfate<br />

Table F<br />

Solubility Guidelines for Aqueous Solutions<br />

Ions That Form<br />

Soluble Compounds<br />

Group 1 ions<br />

(Li + , Na + , etc.)<br />

ammonium (NH 4 + )<br />

nitrate (NO 3 – )<br />

acetate (C 2<br />

H 3<br />

O 2 – or<br />

CH 3<br />

COO – )<br />

hydrogen carbonate<br />

(HCO 3 – )<br />

chlorate (ClO 3 – )<br />

halides (Cl – , Br – , I – )<br />

Exceptions<br />

when combined with<br />

Ag + , Pb 2+ , or Hg 2<br />

2+<br />

sulfates (SO 4 2– ) when combined with Ag + ,<br />

Ca 2+ , Sr 2+ , Ba 2+ , or Pb 2+<br />

Ions That Form<br />

Insoluble Compounds*<br />

Exceptions<br />

carbonate (CO 3 2– ) when combined with Group 1<br />

ions or ammonium (NH 4 + )<br />

chromate (CrO 4 2– ) when combined with Group 1<br />

ions, Ca 2+ , Mg 2+ , or<br />

ammonium (NH 4 + )<br />

phosphate (PO 4 3– ) when combined with Group 1<br />

ions or ammonium (NH 4 + )<br />

sulfide (S 2– ) when combined with Group 1<br />

ions or ammonium (NH 4 + )<br />

hydroxide (OH – ) when combined with Group 1<br />

ions, Ca 2+ , Ba 2+ , Sr 2+ , or<br />

ammonium (NH 4 + )<br />

*compounds having very low solubility in H 2 O<br />

R2


150.<br />

140.<br />

Table G<br />

Solubility Curves at Standard Pressure<br />

KI<br />

NaNO 3<br />

130.<br />

120.<br />

KNO 3<br />

110.<br />

100.<br />

Solubility (g solute/100. g H 2<br />

O)<br />

90.<br />

80.<br />

70.<br />

60.<br />

HCl<br />

NH 4<br />

Cl<br />

KCl<br />

50.<br />

40.<br />

30.<br />

NaCl<br />

KClO 3<br />

NH 3<br />

20.<br />

10.<br />

SO 2<br />

0<br />

0 10. 20. 30. 40. 50. 60. 70. 80. 90. 100.<br />

Temperature (°C)<br />

R3


Table H<br />

Vapor Pressure of Four Liquids<br />

200.<br />

propanone<br />

ethanol<br />

150.<br />

water<br />

Vapor Pressure (kPa)<br />

100.<br />

101.3 kPa<br />

ethanoic<br />

acid<br />

50.<br />

0<br />

0 25 50. 75 100. 125<br />

R4


Table I<br />

Heats of Reaction at 101.3 kPa and 298 K<br />

Reaction<br />

ΔH (kJ)*<br />

CH 4<br />

(g) + 2O 2<br />

(g) CO 2<br />

(g) + 2H 2<br />

O() –890.4<br />

C 3<br />

H 8<br />

(g) + 5O 2<br />

(g) 3CO 2<br />

(g) + 4H 2<br />

O() –2219.2<br />

2C 8<br />

H 18<br />

() + 25O 2<br />

(g) 16CO 2<br />

(g) + 18H 2<br />

O() –10943<br />

2CH 3<br />

OH() + 3O 2<br />

(g) 2CO 2<br />

(g) + 4H 2<br />

O() –1452<br />

C 2<br />

H 5<br />

OH() + 3O 2<br />

(g) 2CO 2<br />

(g) + 3H 2<br />

O() –1367<br />

C 6<br />

H 12<br />

O 6<br />

(s) + 6O 2<br />

(g) 6CO 2<br />

(g) + 6H 2<br />

O() –2804<br />

2CO(g) + O 2<br />

(g) 2CO 2<br />

(g) –566.0<br />

C(s) + O 2<br />

(g) CO 2<br />

(g) –393.5<br />

4Al(s) + 3O 2<br />

(g) 2Al 2<br />

O 3<br />

(s) –3351<br />

N 2<br />

(g) + O 2<br />

(g) 2NO(g) +182.6<br />

N 2<br />

(g) + 2O 2<br />

(g) 2NO 2<br />

(g) +66.4<br />

2H 2<br />

(g) + O 2<br />

(g) 2H 2<br />

O(g) –483.6<br />

2H 2<br />

(g) + O 2<br />

(g) 2H 2<br />

O() –571.6<br />

N 2<br />

(g) + 3H 2<br />

(g) 2NH 3<br />

(g) –91.8<br />

2C(s) + 3H 2<br />

(g) C 2<br />

H 6<br />

(g) –84.0<br />

2C(s) + 2H 2<br />

(g) C 2<br />

H 4<br />

(g) +52.4<br />

2C(s) + H 2<br />

(g) C 2<br />

H 2<br />

(g) +227.4<br />

H 2<br />

(g) + I 2<br />

(g) 2HI(g) +53.0<br />

KNO 3<br />

(s) H 2 O K + (aq) + NO 3 – (aq) +34.89<br />

NaOH(s) H 2 O Na + (aq) + OH – (aq) –44.51<br />

NH 4<br />

Cl(s) H 2 O NH 4 + (aq) + Cl – (aq) +14.78<br />

NH 4<br />

NO 3<br />

(s) H 2 O NH 4 + (aq) + NO 3 – (aq) +25.69<br />

NaCl(s) H 2 O Na + (aq) + Cl – (aq) +3.88<br />

LiBr(s) H 2 O Li + (aq) + Br – (aq) –48.83<br />

H + (aq) + OH – (aq) H 2<br />

O() –55.8<br />

*The ΔH values are based on molar quantities represented in the equations.<br />

A minus sign indicates an exothermic reaction.<br />

Most<br />

Active<br />

Least<br />

Active<br />

Table J<br />

Activity Series**<br />

Metals Nonmetals Most<br />

Active<br />

Li<br />

Rb<br />

K<br />

Cs<br />

Ba<br />

Sr<br />

Ca<br />

Na<br />

Mg<br />

Al<br />

Ti<br />

Mn<br />

Zn<br />

Cr<br />

Fe<br />

Co<br />

Ni<br />

Sn<br />

Pb<br />

H 2<br />

Cu<br />

Ag<br />

Au<br />

F 2<br />

Cl 2<br />

Br 2<br />

I 2<br />

**Activity Series is based on the hydrogen<br />

standard. H 2 is not a metal.<br />

Least<br />

Active<br />

R5


Table K<br />

Common Acids<br />

Table N<br />

Selected Radioisotopes<br />

HCl(aq)<br />

Formula<br />

HNO 2<br />

(aq)<br />

HNO 3<br />

(aq)<br />

H 2<br />

SO 3<br />

(aq)<br />

H 2<br />

SO 4<br />

(aq)<br />

H 3<br />

PO 4<br />

(aq)<br />

H 2<br />

CO 3<br />

(aq)<br />

or<br />

CO 2<br />

(aq)<br />

CH 3<br />

COOH(aq)<br />

or<br />

HC 2<br />

H 3<br />

O 2<br />

(aq)<br />

Name<br />

hydrochloric acid<br />

nitrous acid<br />

nitric acid<br />

sulfurous acid<br />

sulfuric acid<br />

phosphoric acid<br />

carbonic acid<br />

ethanoic acid<br />

(acetic acid)<br />

Nuclide Half-Life Decay<br />

Mode<br />

Nuclide<br />

Name<br />

198 Au 2.695 d β – gold-198<br />

14 C 5715 y β – carbon-14<br />

37 Ca 182 ms β + calcium-37<br />

60 Co 5.271 y β – cobalt-60<br />

137 Cs 30.2 y β – cesium-137<br />

53 Fe 8.51 min β + iron-53<br />

220 Fr 27.4 s α francium-220<br />

3 H 12.31 y β – hydrogen-3<br />

131 I 8.021 d β – iodine-131<br />

37 K 1.23 s β + potassium-37<br />

42 K 12.36 h β – potassium-42<br />

Table L<br />

Common Bases<br />

85 Kr 10.73 y β – krypton-85<br />

16 N 7.13 s β – nitrogen-16<br />

Formula<br />

NaOH(aq)<br />

KOH(aq)<br />

Ca(OH) 2<br />

(aq)<br />

NH 3<br />

(aq)<br />

Name<br />

sodium hydroxide<br />

potassium hydroxide<br />

calcium hydroxide<br />

aqueous ammonia<br />

19 Ne <strong>17</strong>.22 s β + neon-19<br />

32 P 14.28 d β – phosphorus-32<br />

239 Pu 2.410 × 10 4 y α plutonium-239<br />

226 Ra 1599 y α radium-226<br />

222 Rn 3.823 d α radon-222<br />

90 Sr 29.1 y β – strontium-90<br />

Table M<br />

Common Acid–Base Indicators<br />

Approximate<br />

Indicator pH Range Color<br />

for Color Change<br />

Change<br />

methyl orange 3.1–4.4 red to yellow<br />

bromthymol blue 6.0–7.6 yellow to blue<br />

phenolphthalein 8–9 colorless to pink<br />

litmus 4.5–8.3 red to blue<br />

bromcresol green 3.8–5.4 yellow to blue<br />

thymol blue 8.0–9.6 yellow to blue<br />

99 Tc 2.13 × 10 5 y β – technetium-99<br />

232 Th 1.40 × 10 10 y α thorium-232<br />

233 U 1.592 × 10 5 y α uranium-233<br />

235 U 7.04 × 10 8 y α uranium-235<br />

238 U 4.47 × 10 9 y α uranium-238<br />

Source: CRC Handbook of <strong>Chemistry</strong> and Physics, 91 st ed., 2010–2011,<br />

CRC Press<br />

Source: The Merck Index, 14 th ed., 2006, Merck Publishing Group<br />

R6


Table O<br />

Symbols Used in Nuclear <strong>Chemistry</strong><br />

Name Notation Symbol<br />

alpha particle<br />

4<br />

2<br />

He or 4 2 α α<br />

beta particle<br />

0<br />

–1<br />

e or 0<br />

–1 β β–<br />

gamma radiation<br />

0<br />

0<br />

γ γ<br />

neutron<br />

1<br />

0<br />

n n<br />

proton<br />

1<br />

1<br />

H or 1 1 p p<br />

positron<br />

0<br />

+1<br />

e or 0<br />

+1 β β+<br />

Table P<br />

Organic Prefixes<br />

Prefix<br />

meth- 1<br />

eth- 2<br />

prop- 3<br />

but- 4<br />

pent- 5<br />

hex- 6<br />

hept- 7<br />

oct- 8<br />

non- 9<br />

dec- 10<br />

Number of<br />

Carbon Atoms<br />

Table Q<br />

Homologous Series of Hydrocarbons<br />

Name General Examples<br />

Formula Name Structural Formula<br />

R7<br />

alkanes C n<br />

H 2n+2<br />

ethane<br />

alkenes C n<br />

H 2n<br />

ethene<br />

alkynes C n<br />

H 2n–2<br />

ethyne<br />

Note: n = number of carbon atoms<br />

H H<br />

H C C H<br />

H H<br />

H<br />

H<br />

C C<br />

H<br />

H<br />

H C C H


Table R<br />

Organic Functional Groups<br />

Class of<br />

Compound<br />

Functional<br />

Group<br />

General<br />

Formula<br />

Example<br />

halide<br />

(halocarbon)<br />

F (fluoro-)<br />

Cl (chloro-)<br />

Br (bromo-)<br />

I (iodo-)<br />

R X<br />

(X represents<br />

any halogen)<br />

CH 3<br />

CHClCH 3<br />

2-chloropropane<br />

alcohol<br />

OH<br />

R<br />

OH<br />

CH 3<br />

CH 2<br />

CH 2<br />

OH<br />

1-propanol<br />

ether<br />

O<br />

R O R′<br />

CH 3<br />

OCH 2<br />

CH 3<br />

methyl ethyl ether<br />

aldehyde<br />

O<br />

C H<br />

R<br />

O<br />

C H<br />

O<br />

CH 3<br />

CH 2<br />

C H<br />

propanal<br />

ketone<br />

O<br />

C<br />

O<br />

R C R′<br />

O<br />

CH 3<br />

CCH 2<br />

CH 2<br />

CH 3<br />

2-pentanone<br />

organic acid<br />

O<br />

C OH<br />

R<br />

O<br />

C OH<br />

O<br />

CH 3<br />

CH 2<br />

C OH<br />

propanoic acid<br />

ester<br />

O<br />

C O<br />

O<br />

R C O R′<br />

O<br />

CH 3<br />

CH 2<br />

COCH 3<br />

methyl propanoate<br />

amine<br />

N<br />

R<br />

R′<br />

N R′′<br />

CH 3<br />

CH 2<br />

CH 2<br />

NH 2<br />

1-propanamine<br />

amide<br />

O<br />

C NH<br />

R<br />

O R′<br />

C NH<br />

O<br />

CH 3<br />

CH 2<br />

C NH 2<br />

propanamide<br />

Note: R represents a bonded atom or group of atoms.<br />

R8


0<br />

6.941<br />

+1<br />

Li<br />

3<br />

2-1<br />

Na<br />

39.0983<br />

K +1<br />

19<br />

2-8-8-1<br />

85.4678 +1<br />

Rb<br />

Cs<br />

(223)<br />

Fr<br />

87<br />

-18-32-18-8-1<br />

+1<br />

Ra<br />

88<br />

-18-32-18-8-2<br />

39<br />

138.9055<br />

La<br />

57<br />

2-8-18-18-9-2<br />

+2 (227)<br />

Ac<br />

89<br />

-18-32-18-9-2<br />

47.867<br />

Ti<br />

22<br />

2-8-10-2<br />

91.224<br />

Zr<br />

40<br />

2-8-18-10-2<br />

+3 <strong>17</strong>8.49<br />

Hf<br />

72<br />

*18-32-10-2<br />

+3 (261)<br />

Rf<br />

104<br />

+2<br />

+3<br />

+4<br />

+4<br />

+4<br />

50.9415<br />

V<br />

23<br />

2-8-11-2<br />

+2<br />

+3<br />

+4<br />

+5<br />

51.996<br />

Cr<br />

24<br />

2-8-13-1<br />

95.94<br />

Mo<br />

42<br />

2-8-18-13-1<br />

183.84<br />

W<br />

74<br />

-18-32-12-2<br />

+2<br />

+3<br />

+6<br />

+6<br />

+6<br />

54.9380<br />

Mn<br />

25<br />

2-8-13-2<br />

+2<br />

+3<br />

+4<br />

+7<br />

55.845<br />

Fe<br />

26<br />

2-8-14-2<br />

+2<br />

+3 58.9332<br />

Co<br />

27<br />

2-8-15-2<br />

+2<br />

+3<br />

58.693<br />

Ni<br />

28<br />

2-8-16-2<br />

+2<br />

+3 63.546 Cu<br />

2-8-18-1<br />

107.868<br />

Ag<br />

47<br />

2-8-18-18-1<br />

79<br />

+1<br />

+2<br />

+1<br />

65.409<br />

Zn<br />

30<br />

2-8-18-2<br />

10.81<br />

+3 12.011<br />

B<br />

5<br />

2-3<br />

26.98154<br />

Al<br />

13<br />

2-8-3<br />

+2 69.723<br />

Ga<br />

31<br />

2-8-18-3<br />

+3<br />

+3<br />

–4<br />

+2<br />

+4<br />

C<br />

6<br />

2-4<br />

28.0855<br />

Si<br />

14<br />

2-8-4<br />

72.64<br />

Ge<br />

32<br />

2-8-18-4<br />

Pb<br />

–4<br />

+2<br />

+4<br />

+2<br />

+4<br />

74.9216<br />

As<br />

33<br />

2-8-18-5<br />

Sb<br />

–3<br />

+3<br />

15.9994 O<br />

–2 18.9984<br />

8<br />

2-6 2-7<br />

78.96<br />

Se<br />

34<br />

2-8-18-6<br />

127.60<br />

Te<br />

52<br />

2-8-18-18-6<br />

(209)<br />

Po<br />

84<br />

-18-32-18-6<br />

–2<br />

+4<br />

+6<br />

–2<br />

+4<br />

+6<br />

+2<br />

+4<br />

F<br />

79.904<br />

Br<br />

35<br />

2-8-18-7<br />

126.904<br />

l<br />

53<br />

2-8-18-18-7<br />

(210)<br />

At<br />

85<br />

-18-32-18-7<br />

( ? )<br />

Uus<br />

1<strong>17</strong><br />

4.00260 0<br />

He<br />

2<br />

2<br />

–1 20.180<br />

Ne<br />

10<br />

2-8<br />

0<br />

22.98977<br />

11<br />

2-8-1<br />

1<br />

1.00794 +1<br />

–1<br />

H<br />

1<br />

1<br />

1<br />

37<br />

2-8-18-8-1<br />

–1<br />

+1<br />

+5<br />

–1<br />

+1<br />

+5<br />

+7<br />

83.798<br />

Kr<br />

36<br />

2-8-18-8<br />

131.29<br />

Xe<br />

54<br />

2-8-18-18-8<br />

(222)<br />

Rn<br />

86<br />

-18-32-18-8<br />

0<br />

+2<br />

0<br />

+2<br />

+4<br />

+6<br />

0<br />

132.905<br />

55<br />

2-8-18-18-8-1<br />

Symbol<br />

Relative atomic masses are based<br />

Group on 12 C = 12 (exact)<br />

Group<br />

2<br />

13 14 15 16 <strong>17</strong> 18<br />

Atomic Number<br />

+1<br />

+1<br />

9.01218 +2<br />

Be<br />

4<br />

2-2<br />

24.305<br />

Mg<br />

12<br />

2-8-2<br />

40.08<br />

Ca<br />

20<br />

2-8-8-2<br />

87.62<br />

Sr<br />

38<br />

2-8-18-8-2<br />

137.33<br />

Ba<br />

56<br />

2-8-18-18-8-2<br />

(226)<br />

+2<br />

+2<br />

+2<br />

+2<br />

3<br />

44.9559<br />

Sc<br />

21<br />

2-8-9-2<br />

88.9059<br />

Y<br />

2-8-18-9-2<br />

+3<br />

+3<br />

4<br />

KEY<br />

92.9064<br />

Nb +3<br />

+5<br />

41<br />

2-8-18-12-1<br />

180.948<br />

Ta<br />

73<br />

-18-32-11-2<br />

(262)<br />

105<br />

5<br />

Periodic Table of the Elements<br />

Atomic Mass<br />

Electron Configuration<br />

+4<br />

Db<br />

+5<br />

6<br />

(266)<br />

Sg<br />

106<br />

12.011 2-4<br />

–4<br />

6<br />

C<br />

+2<br />

+4<br />

(98)<br />

Tc<br />

43<br />

2-8-18-13-2<br />

186.207<br />

Re<br />

75<br />

-18-32-13-2<br />

(272)<br />

Bh<br />

107<br />

7<br />

Group<br />

+4<br />

+6<br />

+7<br />

+4<br />

+6<br />

+7<br />

8<br />

101.07<br />

Ru<br />

44<br />

2-8-18-15-1<br />

190.23<br />

Os<br />

76<br />

-18-32-14-2<br />

(277)<br />

Hs<br />

108<br />

+3<br />

+3<br />

+4<br />

Selected Oxidation States<br />

Note: Numbers in parentheses<br />

are mass numbers of the most<br />

stable or common isotope.<br />

9<br />

102.906<br />

Rh<br />

45<br />

2-8-18-16-1<br />

192.2<strong>17</strong><br />

Ir<br />

77<br />

-18-32-15-2<br />

(276)<br />

Mt<br />

109<br />

+3<br />

+3<br />

+4<br />

106.42<br />

Pd<br />

46<br />

2-8-18-18<br />

195.08<br />

Pt<br />

78<br />

-18-32-<strong>17</strong>-1<br />

+2<br />

+4<br />

+2<br />

+4<br />

196.967<br />

Au<br />

-18-32-18-1<br />

(281)<br />

Ds (280) Rg<br />

110<br />

10<br />

29<br />

111<br />

11 12<br />

+1<br />

+3<br />

112.41<br />

Cd<br />

48<br />

2-8-18-18-2<br />

200.59<br />

Hg<br />

80<br />

-18-32-18-2<br />

(285)<br />

Cn<br />

112<br />

+2 114.818<br />

In<br />

+1<br />

+2<br />

49<br />

2-8-18-18-3<br />

204.383<br />

Tl<br />

81<br />

-18-32-18-3<br />

(284)<br />

Uut<br />

113**<br />

+3<br />

+1<br />

+3<br />

118.71<br />

Sn<br />

50<br />

2-8-18-18-4<br />

207.2<br />

82<br />

-18-32-18-4<br />

(289)<br />

Uuq<br />

114<br />

+2<br />

+4<br />

+2<br />

+4<br />

14.0067 –3<br />

–2<br />

N<br />

–1<br />

7<br />

2-5<br />

30.97376<br />

P<br />

15<br />

2-8-5<br />

121.760<br />

51<br />

2-8-18-18-5<br />

208.980<br />

Bi<br />

83<br />

-18-32-18-5<br />

(288)<br />

Uup<br />

115<br />

+1<br />

+2<br />

+3<br />

+4<br />

+5<br />

–3<br />

+3<br />

+5<br />

+5<br />

–3<br />

+3<br />

+5<br />

+3<br />

+5<br />

32.065<br />

S<br />

16<br />

2-8-6<br />

(292)<br />

Uuh<br />

116<br />

–2<br />

+4<br />

+6<br />

35.453<br />

Cl<br />

<strong>17</strong><br />

2-8-7<br />

–1<br />

+1<br />

+5<br />

+7<br />

39.948<br />

Ar<br />

18<br />

2-8-8<br />

18<br />

(294)<br />

Uuo<br />

118<br />

140.116<br />

Ce<br />

58<br />

232.038<br />

Th<br />

90<br />

+3<br />

+4<br />

140.908<br />

Pr +3<br />

59<br />

144.24<br />

Nd<br />

60<br />

+4 231.036<br />

Pa +4 238.029 +5<br />

U +3<br />

+4<br />

+5<br />

+6<br />

91<br />

92<br />

+3<br />

(145)<br />

Pm<br />

61<br />

+3<br />

150.36<br />

Sm<br />

62<br />

+2<br />

+3<br />

151.964<br />

Eu<br />

63<br />

+2<br />

+3<br />

157.25<br />

Gd<br />

64<br />

+3<br />

158.925<br />

(237)Np (244) Pu (243) Am (247) Cm +3 (247) Bk +3<br />

+3<br />

+4<br />

+5<br />

+6<br />

93 94<br />

+3<br />

+4<br />

+5<br />

+6<br />

65<br />

+3<br />

+4<br />

+5<br />

+6<br />

95 96 97<br />

Tb<br />

+3<br />

+4<br />

162.500<br />

Dy<br />

66<br />

(251)<br />

+3<br />

164.930<br />

Ho<br />

67<br />

+3<br />

167.259<br />

Er<br />

68<br />

Cf +3 (252) Es (257) Fm<br />

100<br />

98 99<br />

+3<br />

+3<br />

+3<br />

168.934<br />

Tm +3<br />

69<br />

(258)<br />

Md<br />

101<br />

+2<br />

+3<br />

<strong>17</strong>3.04<br />

Yb<br />

70<br />

(259)<br />

No<br />

102<br />

+2<br />

+3<br />

+2<br />

+3<br />

<strong>17</strong>4.9668<br />

Lu<br />

71<br />

(262)<br />

Lr<br />

103<br />

+3<br />

+3<br />

*denotes the presence of (2-8-) for elements 72 and above<br />

**The systematic names and symbols for elements of atomic numbers 113 and above<br />

will be used until the approval of trivial names by IUPAC.<br />

Source: CRC Handbook of <strong>Chemistry</strong> and Physics, 91 st ed., 2010–2011, CRC Press<br />

9<br />

R9<br />

Period<br />

1<br />

2<br />

3<br />

4<br />

5<br />

6<br />

7


Table S<br />

Properties of Selected Elements<br />

First<br />

Atomic Symbol Name Ionization<br />

Electro- Melting Boiling* Density** Atomic<br />

Number Energy negativity Point Point (g/cm 3 ) Radius<br />

(kJ/mol) (K) (K) (pm)<br />

1 H hydrogen 1312 2.2 14 20. 0.000082 32<br />

2 He helium 2372 — — 4 0.000164 37<br />

3 Li lithium 520. 1.0 454 1615 0.534 130.<br />

4 Be beryllium 900. 1.6 1560. 2744 1.85 99<br />

5 B boron 801 2.0 2348 4273 2.34 84<br />

6 C carbon 1086 2.6 — — .— 75<br />

7 N nitrogen 1402 3.0 63 77 0.001145 71<br />

8 O oxygen 1314 3.4 54 90. 0.001308 64<br />

9 F fluorine 1681 4.0 53 85 0.001553 60.<br />

10 Ne neon 2081 — 24 27 0.000825 62<br />

11 Na sodium 496 0.9 371 1156 0.97 160.<br />

12 Mg magnesium 738 1.3 923 1363 1.74 140.<br />

13 Al aluminum 578 1.6 933 2792 2.70 124<br />

14 Si silicon 787 1.9 1687 3538 2.3296 114<br />

15 P phosphorus (white) 1012 2.2 3<strong>17</strong> 554 1.823 109<br />

16 S sulfur (monoclinic) 1000. 2.6 388 718 2.00 104<br />

<strong>17</strong> Cl chlorine 1251 3.2 <strong>17</strong>2 239 0.002898 100.<br />

18 Ar argon 1521 — 84 87 0.001633 101<br />

19 K potassium 419 0.8 337 1032 0.89 200.<br />

20 Ca calcium 590. 1.0 1115 <strong>17</strong>57 1.54 <strong>17</strong>4<br />

21 Sc scandium 633 1.4 1814 3109 2.99 159<br />

22 Ti titanium 659 1.5 1941 3560. 4.506 148<br />

23 V vanadium 651 1.6 2183 3680. 6.0 144<br />

24 Cr chromium 653 1.7 2180. 2944 7.15 130.<br />

25 Mn manganese 7<strong>17</strong> 1.6 1519 2334 7.3 129<br />

26 Fe iron 762 1.8 1811 3134 7.87 124<br />

27 Co cobalt 760. 1.9 <strong>17</strong>68 3200. 8.86 118<br />

28 Ni nickel 737 1.9 <strong>17</strong>28 3186 8.90 1<strong>17</strong><br />

29 Cu copper 745 1.9 1358 2835 8.96 122<br />

30 Zn zinc 906 1.7 693 1180. 7.134 120.<br />

31 Ga gallium 579 1.8 303 2477 5.91 123<br />

32 Ge germanium 762 2.0 1211 3106 5.3234 120.<br />

33 As arsenic (gray) 944 2.2 1090. — 5.75 120.<br />

34 Se selenium (gray) 941 2.6 494 958 4.809 118<br />

35 Br bromine 1140. 3.0 266 332 3.1028 1<strong>17</strong><br />

36 Kr krypton 1351 — 116 120. 0.003425 116<br />

37 Rb rubidium 403 0.8 312 961 1.53 215<br />

38 Sr strontium 549 1.0 1050. 1655 2.64 190.<br />

39 Y yttrium 600. 1.2 <strong>17</strong>95 3618 4.47 <strong>17</strong>6<br />

40 Zr zirconium 640. 1.3 2128 4682 6.52 164<br />

R10


First<br />

Atomic Symbol Name Ionization<br />

Electro- Melting Boiling* Density** Atomic<br />

Number Energy negativity Point Point (g/cm 3 ) Radius<br />

(kJ/mol) (K) (K) (pm)<br />

41 Nb niobium 652 1.6 2750. 50<strong>17</strong> 8.57 156<br />

42 Mo molybdenum 684 2.2 2896 4912 10.2 146<br />

43 Tc technetium 702 2.1 2430. 4538 11 138<br />

44 Ru ruthenium 710. 2.2 2606 4423 12.1 136<br />

45 Rh rhodium 720. 2.3 2237 3968 12.4 134<br />

46 Pd palladium 804 2.2 1828 3236 12.0 130.<br />

47 Ag silver 731 1.9 1235 2435 10.5 136<br />

48 Cd cadmium 868 1.7 594 1040. 8.69 140.<br />

49 In indium 558 1.8 430. 2345 7.31 142<br />

50 Sn tin (white) 709 2.0 505 2875 7.287 140.<br />

51 Sb antimony (gray) 831 2.1 904 1860. 6.68 140.<br />

52 Te tellurium 869 2.1 723 1261 6.232 137<br />

53 I iodine 1008 2.7 387 457 4.933 136<br />

54 Xe xenon 1<strong>17</strong>0. 2.6 161 165 0.005366 136<br />

55 Cs cesium 376 0.8 302 944 1.873 238<br />

56 Ba barium 503 0.9 1000. 2<strong>17</strong>0. 3.62 206<br />

57 La lanthanum 538 1.1 1193 3737 6.15 194<br />

Elements 58–71 have been omitted.<br />

72 Hf hafnium 659 1.3 2506 4876 13.3 164<br />

73 Ta tantalum 728 1.5 3290. 5731 16.4 158<br />

74 W tungsten 759 1.7 3695 5828 19.3 150.<br />

75 Re rhenium 756 1.9 3458 5869 20.8 141<br />

76 Os osmium 814 2.2 3306 5285 22.587 136<br />

77 Ir iridium 865 2.2 2719 4701 22.562 132<br />

78 Pt platinum 864 2.2 2041 4098 21.5 130.<br />

79 Au gold 890. 2.4 1337 3129 19.3 130.<br />

80 Hg mercury 1007 1.9 234 630. 13.5336 132<br />

81 Tl thallium 589 1.8 577 <strong>17</strong>46 11.8 144<br />

82 Pb lead 716 1.8 600. 2022 11.3 145<br />

83 Bi bismuth 703 1.9 544 1837 9.79 150.<br />

84 Po polonium 812 2.0 527 1235 9.20 142<br />

85 At astatine — 2.2 575 — — 148<br />

86 Rn radon 1037 — 202 211 0.009074 146<br />

87 Fr francium 393 0.7 300. — — 242<br />

88 Ra radium 509 0.9 969 — 5 211<br />

89 Ac actinium 499 1.1 1323 3471 10. 201<br />

Elements 90 and above have been omitted.<br />

*boiling point at standard pressure<br />

**density of solids and liquids at room temperature and density of gases at 298 K and 101.3 kPa<br />

— no data available<br />

Source: CRC Handbook for <strong>Chemistry</strong> and Physics, 91 st ed., 2010–2011, CRC Press<br />

R11


Table T<br />

Important Formulas and Equations<br />

d = density<br />

m<br />

Density d = m = mass<br />

V<br />

V = volume<br />

Mole Calculations number of moles =<br />

given mass<br />

gram-formula mass<br />

measured value – accepted value<br />

Percent Error % error = × 100<br />

accepted value<br />

mass of part<br />

Percent Composition % composition by mass = × 100<br />

mass of whole<br />

mass of solute<br />

parts per million = × 1000000<br />

mass of solution<br />

Concentration<br />

molarity =<br />

moles of solute<br />

liter of solution<br />

Combined Gas Law<br />

P<br />

P = pressure<br />

1<br />

V 1<br />

P<br />

= 2<br />

V 2<br />

V = volume<br />

T 1<br />

T 2 T = temperature<br />

M A<br />

= molarity of H + M B<br />

= molarity of OH –<br />

Titration M A<br />

V A<br />

= M B<br />

V B<br />

V A<br />

= volume of acid V B<br />

= volume of base<br />

q = mCΔT q = heat H f<br />

= heat of fusion<br />

Heat q = mH f<br />

m = mass H v<br />

= heat of vaporization<br />

q = mH v<br />

C=specific heat capacity<br />

ΔT = change in temperature<br />

Temperature<br />

K = °C + 273<br />

K = kelvin<br />

°C = degree Celsius<br />

R12


Collier County CHEMISTRY EXAM FORMULA AND RESOURCE PACKET<br />

GENERAL<br />

D m V<br />

[ ExperimentalValue AcceptedVa lue]<br />

% error <br />

x100<br />

AcceptedVa lue<br />

% yield <br />

ExperimentalYield<br />

TheoreticalYield<br />

x100<br />

CONCENTRATIONS<br />

moles of solute<br />

M = Molarity <br />

liters of solution<br />

KEY<br />

P = pressure<br />

V = volume<br />

T = temperature<br />

n = number of moles<br />

m = mass<br />

M = molar mass (grams/mole)<br />

D = density<br />

KE = kinetic energy<br />

Avogadro’s Number = 6.02 x 10 23<br />

GASES, LIQUIDS, SOLUTIONS<br />

m = Molality <br />

M1V1 M2V2<br />

S1<br />

P1<br />

S 2<br />

P 2<br />

ACID/BASE<br />

pH = - log[H + ]<br />

[H + ]=10 -pH<br />

moles of solute<br />

kilograms of solvent<br />

<br />

Gas constant<br />

R 8.314 L kPa L atm L mmHg<br />

0.0821 62.4<br />

K mol K mol K mol<br />

1 atm = 760 mmHg = 760 torr = 101.3 kPa<br />

K = o C + 273<br />

o C = K - 273<br />

STP = Standard Temperature and Pressure = 0 o C<br />

and 1 atm<br />

P V<br />

1 1<br />

<br />

P2V<br />

2<br />

pOH = - log [OH - ]<br />

[OH - ]= 10 -pOH<br />

pH + pOH = 14<br />

Kw = [H + ] x [OH - ] = 1.0 x 10 -14 M 2<br />

V<br />

T<br />

1<br />

1<br />

P<br />

T<br />

1<br />

1<br />

V<br />

<br />

T<br />

P<br />

<br />

T<br />

2<br />

2<br />

2<br />

2<br />

Or V1T2 = V2T1<br />

Or P1T2 = P2T1<br />

THERMOCHEMISTRY<br />

ΔH= mCΔT, where ΔT = T f - T<br />

P1V<br />

1<br />

T<br />

1<br />

<br />

P2V<br />

2<br />

T<br />

2<br />

Or<br />

P1V1T2=P2V2T1<br />

q = mCΔT<br />

PV<br />

nRT<br />

Specific Heat of Water = 4.18 J/g*˚C or 1.0 cal/g*˚C<br />

Specific Heat of Ice = 2.1 J/g*˚C or 0.5 cal/g*˚C<br />

Specific Heat of Steam = 2.0 J/g*˚C or 0.4 cal/g*˚C<br />

P<br />

Total<br />

P<br />

1<br />

P<br />

2<br />

Rate A<br />

Rate B<br />

...<br />

<br />

Molar MassB<br />

Molar MassA<br />

R13


CHEMISTRY EXAM FORMULA AND RESOURCE PACKET<br />

Solubility of Compounds at 25 o C and 1 atm<br />

acetate<br />

bromide<br />

carbonate<br />

chlorate<br />

chloride<br />

hydroxide<br />

iodide<br />

nitrate<br />

oxide<br />

perchlorate<br />

phosphate<br />

sulfate<br />

sulfide<br />

aluminum S S - S S I S S I S I S d<br />

ammonium S S S S S S S S - S S S S<br />

barium S S I S S S S S sS S I I d<br />

calcium S S I S S S S S sS S I sS I<br />

copper(II) S S - S S I S S I S I S I<br />

iron(II) S S I S S I S S I S I S I<br />

iron(III) S S - S S I S S I S I sS d<br />

lithium S S sS S S S S S S S sS S S<br />

magnesium S S I S S I S S I S I S d<br />

potassium S S S S S S S S S S S S S<br />

silver sS I I S I - I S I S I sS I<br />

sodium S S S S S S S S S S S S S<br />

strontium S S I S S S S S S S I I I<br />

zinc S S I S S I S S I S I S I<br />

S=soluble<br />

sS = slightly soluble in water<br />

I = insoluble in water<br />

d = decomposes in water<br />

- = no such compound<br />

R14


CHEMISTRY EXAM FORMULA AND RESOURCE PACKET<br />

Common Polyatomic Ions<br />

1- Charge 2- Charge 3- Charge<br />

Formula Name Formula Name Formula Name<br />

Dihydrogen<br />

Phosphate<br />

Hydrogen<br />

phosphate<br />

Phosphite<br />

Acetate Oxalate Phosphate<br />

Hydrogen<br />

sulfite<br />

Sulfite<br />

Hydrogen<br />

sulfate<br />

Sulfate<br />

Hydrogen<br />

carbonate<br />

Carbonate<br />

Nitrite Chromate 1+ Charge<br />

Nitrate Dichromate Formula Name<br />

Cyanide Silicate Ammonium<br />

Hydroxide<br />

Permanganate<br />

Hypochlorite<br />

Chlorite<br />

Chlorate<br />

Perchlorate<br />

R15


Activity Series of Metals<br />

Name<br />

Symbol<br />

D<br />

Lithium<br />

Li<br />

e<br />

Potassium<br />

K<br />

c<br />

r<br />

Barium<br />

Ba<br />

e<br />

Calcium<br />

Ca<br />

a<br />

Sodium<br />

Na<br />

s<br />

i<br />

Magnesium<br />

Mg<br />

n<br />

Aluminum<br />

Al<br />

g<br />

Zinc<br />

Zn<br />

Iron<br />

Fe<br />

A<br />

c<br />

Nickel<br />

Ni<br />

t<br />

Tin<br />

Sn<br />

i<br />

v<br />

Lead<br />

Pb<br />

i<br />

(Hydrogen)<br />

(H)*<br />

t<br />

Copper<br />

Cu<br />

y<br />

Mercury<br />

Hg<br />

Silver<br />

Ag<br />

Gold<br />

Au<br />

*Metals from Li to Na will replace H from acids and water; from Mg to<br />

Pb they will replace H from acids only.<br />

Decreasing<br />

Activity<br />

Activity Series of Nonmetal (Halogens)<br />

Name<br />

Symbol<br />

Fluorine F 2<br />

Chlorine Cl 2<br />

Bromine Br 2<br />

Iodine I 2<br />

R16

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