Chem 111 Quiz 1 – September 9, 2005 Name: Multiple Choice ...

Chem 111
Quiz 1 – September 9, 2005
Multiple Choice:
Name: _______________________________
__C_ 1. The prefix nano means:
a) 10 -3 c) 10 -9
b) 10 -6 d) 10 9
__D_ 2. When rounded to 4 significant figures, the number 56.65512 becomes:
a) 56.65 c) 56.60
b) 56.6551 d) 56.66
__A_ 3. A student calculation indicates that 4.32 x 10 2 grams of a compound will be needed. The
scale should read:
a) 432 g c) 0.432 g
b) 43.2 g d) 0.0432 g
__B_ 4. Using the rules of significant figures, the sum of 12.67 + 13.005 is:
a) 25.675 c) 20
b) 25.68 d) 25.7
__A_ 5. One of the isotopes of mercury is 200 Hg. The number of protons, neutrons and electrons,
respectively, in this atom is:
a) 80, 120, 80 c) 80, 80, 120
b) 120, 80, 80 d) 80, 200, 80
__C_ 6. The elements Cl and I have similar properties because they:
a) Are both metals
b) Are in the same chemical period
c) Have the same number of electrons in their outermost energy level
d) Have the same number of isotopes
__B_ 7. Which of the following colors of light in the visible range of the electromagnetic
spectrum has the highest energy?
a) Red c) orange
b) Green d) yellow
__B_ 8. When light is emitted by an atom in a flame,
a) an electron jumps to a higher energy level
b) an electron falls to a lower energy level
c) a proton jumps to a higher energy level
d) a neutron falls to a higher energy level
__C_ 9. The correct scientific notation that describes 187,000 is:
a) 1.87 x 10 3 c) 1.87 x 10 5
b) 1.87 x 10 -3 d) 1.87 x 10 -5

__D_10. According to modern theory, the smallest particle of an element is:
a) A proton c) an electron
b) A molecule d) an atom
Short Answer:
11. Sudafed is one of the brand names for pseudoephedrine, a nasal decongestant. Each mole of
pseudoephedrine has a mass of 165.2 grams. The usual dosage for adults is 0.060 grams every
four to six hours. Given that 1 mole is 6.02 x 10 23 molecules, how many molecules of
pseudoephedrine are in a typical adult dose? (5 points)
0.060 g x
1 mole
165.2 g x 6.02 x 1023 molecules
1 mole
= 2.19 x 10 20 molecules
12. a) What element’s atom contain 12 protons, 12 neutrons and 12 electrons? _____Mg____
b) What element’s atoms contain 34 protons, 45 neutrons and 34 electrons? _____Se____
c) What isotope contains 17 protons, 17 electrons and 18 neutrons? ____ 35 Cl____
13. When sodium ions are excited in a flame, yellow light is emitted. But when barium is
used, the color of light is green. How does the modern theory of the atom explain this
difference? (2 points)
Different colors being emitted means that different energies are being released by the
electrons in Ba and Na. The energy differences are due to different distances that the
electrons fall as they return to the non-excited state. The electrons in Ba must be falling
‘farther’ than electrons in Na.