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1st Semester Notebook

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Juan Roque<br />

Chemistry notebook


Chapter 1<br />

Unit 1<br />

Introduction to Chemistry<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


Unit 3<br />

Chapter 25 Nuclear Chemistry<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 />

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 />

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


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 />

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 />

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 />

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 />

Atom<br />

Electron<br />

Element<br />

Compound<br />

51


Name ____________________<br />

Juan Roque<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 />

Low __________, frequency Long wavelength<br />

High frequency, Short ______________<br />

wavelengths<br />

Radio Waves<br />

microwaves Infra-red Visible Light Ultra-Violet X-rays<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 _________, Wifi _______ speed cameras and _________. 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 ___ CDplayers 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 ________________ radioactive substances. We can use them to kill ________ cancer cells,<br />

which is called R_______________ adiotherapy .<br />

9. My Quiz score is ____%. 94<br />

52


10. Name ________________________________<br />

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

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

by number of astronomical processesUsed to kill cancer cells<br />

Gamma rays<br />

X-rays<br />

Ultra-violet<br />

Visible light<br />

Infra-red<br />

microwaves<br />

Radio waves<br />

very high-energy electrons are made<br />

When electrons strike a metal target<br />

electrons are liberated from heated<br />

filament and accelerated by high<br />

voltage towards trget.<br />

Given off by the sun in large<br />

quantities<br />

special lamps such as sun beds<br />

white ligth is actually made up of a<br />

whole range of colours, mixed together.<br />

Radiotherapy<br />

Kill microbes and used to sterilise food<br />

To see inside people<br />

airport security<br />

atronomers<br />

Sun tan and detecting forged bank<br />

notes<br />

kill microbes<br />

produces vitamin D<br />

food drug companies sterilise their products<br />

to see things<br />

CD and DVD players<br />

remote controls, video recorders<br />

below the visible red light<br />

heal sprot injuries<br />

anthing else that is given off by hot objects<br />

night sights<br />

extremely high frequency radio waves,<br />

made by various amount of transmitters<br />

Made by various types of transmitters,<br />

depending on the wavelength<br />

mobile phones<br />

wifi<br />

speed cameras<br />

radar<br />

mainly used for communication<br />

Can cause cell damage<br />

cancer<br />

mutations<br />

can cause cell damage<br />

cancer<br />

Large doses can damage<br />

retin in the eyes<br />

can cause sunburn and<br />

skin cancer<br />

can damage the retina<br />

of the eyes<br />

looking at the sun<br />

too much and you can<br />

overheat<br />

ovrexposure can cause<br />

cateracts<br />

large doses can cause<br />

cancer and disorders<br />

_____ Frequency _____ frequency,<br />

Short wavelength ______ Wavelength<br />

53


Learning Goal for this section:<br />

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

Notes Section:<br />

Alpha particles He 4 goes through alpha<br />

2 238<br />

92 Uranium ><br />

down by 2<br />

protons><br />

234<br />

90 Thorium<br />

+<br />

4<br />

2 He<br />

Beta Particle<br />

up by 1<br />

negative<br />

electron<br />

6p<br />

8n<br />

14<br />

6 Carbon<br />

converting nuetron to proton<br />

carbon 14 turns into nitrogen<br />

14<br />

Nitrogen + negative electron<br />

7<br />

positive<br />

electron<br />

positron<br />

5p<br />

3n<br />

8<br />

5 Be > 8<br />

Be + e+<br />

4<br />

4p<br />

4n<br />

Gamma Energy<br />

always associatied with alpha particle or beta<br />

Half-LIfe 100g start 20min<br />

50g 20min 50g of something else<br />

25 40min 75g of something else<br />

it decays and becomes something else<br />

12.5 60min 87.5g of something else<br />

still 100g but of something else<br />

0.75 120min<br />

93.75 of something else<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.<br />

55


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


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.<br />

57


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

Distinguish between bonding forces holding compounds together and other attractive forces, including hydrogen bonding<br />

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


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 />

61


The Learning Goal for this assignment is:<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 />

metal and nonmetal make a ionic bond<br />

metal and metal make a covalent bond<br />

left side metal right side nonmetal<br />

C^2H^6O<br />

flourine most electronegative and hydrogen is right above it.<br />

1) C2 x 4 8<br />

H^6 x 1 6<br />

O1 x 6 8 = 25<br />

5)<br />

2) C^2 x 8 16<br />

H^6 x 2 12<br />

O^1 x 8 8 = 36<br />

3) 36-20=16e-<br />

4) 2/ 16= 8 bonds<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.<br />

65


Linear<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

sp AX 2 none 180<br />

BeCl 2<br />

Berylium<br />

dicloride<br />

Cl<br />

Be<br />

Cl<br />

element bond lone pair<br />

C<br />

66


Trigonal planal<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

sp 2 AX 3 none 60<br />

BF 3<br />

F<br />

B<br />

Boron triflouride<br />

F<br />

F<br />

element bond lone pair<br />

C<br />

67


Trigonal planar<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

sp 3 AX 2 E 2 2 104<br />

OF 2<br />

Oxygen diflouride<br />

O<br />

F<br />

F<br />

element bond lone pair<br />

C<br />

68


Tetrahedral<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

sp 3 AX 4 none 109.5<br />

PO 4<br />

3-<br />

Phosphate<br />

O<br />

O<br />

P<br />

5-5=0<br />

O<br />

6-6=0<br />

O<br />

6-7=1-<br />

element bond lone pair<br />

C<br />

69


Trigonal Pyramidal<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

sp 3 AX 3 E 2 104.5<br />

PH 3<br />

Phosphorous trihydride<br />

H<br />

P<br />

H<br />

H<br />

element bond lone pair<br />

C<br />

70


linear<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

sp AX 2 2 180<br />

O 3<br />

trioxide<br />

O<br />

O<br />

O<br />

element bond lone pair<br />

C<br />

71


Trigonal Bi pyramidal<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

sp 3 d AX 5 none 120/90<br />

PCl 5<br />

Phosphorous<br />

pentacloride<br />

Cl<br />

Cl<br />

Cl<br />

P<br />

Cl<br />

Cl<br />

element bond lone pair<br />

C<br />

C<br />

72


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 trifloride<br />

F<br />

Cl<br />

F<br />

F<br />

element bond lone pair<br />

C<br />

73


Octahedral<br />

Molecular Geometry<br />

Orbital Equation Lone Pairs Angle<br />

sp 3 d 2 AX 6 none 90<br />

SF 6<br />

Sulfur hexafluoride<br />

F<br />

F<br />

F<br />

S<br />

F<br />

F<br />

F<br />

element bond lone pair<br />

74


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 tetrafluoride<br />

ion<br />

Cl<br />

Cl<br />

I<br />

Cl<br />

Cl<br />

element bond lone pair<br />

C<br />

75


Orbitals Equation Lone Pairs<br />

Angle<br />

Name<br />

Sp 3 d AX5 none 120/90 Phosphorous Penta Chloride<br />

Sp 3 d 2 AX6 none 90<br />

Sulfur hexafluoride<br />

Sp 3 d AX3E2 2 90<br />

Chlorine trifluoride<br />

sp AX2 2 180<br />

Trioxide<br />

Sp 3 AX3E 2 104.5<br />

Phosphorous trihydride<br />

Sp 3 AX4 none 109.5<br />

Phosphorous tetroxide<br />

Sp 3 d 2 AX4E2 2 90<br />

Iodine tetrafluoride ion<br />

Sp 3 AX2E2 2 104<br />

Oxygen difluoride<br />

Sp 2 AX3 none 60<br />

Boron trifluoride<br />

sp AX2 none 180<br />

Beryllium dichloride<br />

78


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-<br />

77


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 />

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 />

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


http://www.bbc.co.uk/education/guides/zm9hvcw/revision<br />

students will learn what effects functional groups have on<br />

organic compounds and how chemical reactinos are used in<br />

organic compounds.<br />

A homologous series is a family of hydrocarbons with similar<br />

chemical properties who share the same genral formula.<br />

The general formula of the alkanes is CnH2n+2<br />

methane- (natural gases) cooking, heating<br />

propane- used in gas cylinders for BBQ etc<br />

octane- used in petrol for cars.<br />

The longest unbranched chain containing the functional group is th<br />

parent molecule, or simply the longest unbranched chain for alkane<br />

rememeber that, the longest chain can go round a bend.<br />

80


5 with<br />

double bond<br />

2 without<br />

81

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