CHEM 1210 EXAM 2 FALL 2012
You will have 55 minutes to complete this exam.
The exam has 5 pages and the Periodic Table Reference page.
When you are told to do so, tear off the Periodic Table cover sheet and use it throughout the exam. You must turn in BOTH the Periodic Table and the completed exam at the end of the time period.
Given:
N
A
= 6.022×10 23
= 1 mole
Electronegativity Values:
As- 2.18
O- 3.14
P- 2.19
Cl- 3.16
F- 3.98
C-2.55
1

2

3

Name___________________________________ PID__________________________
Circle your LECTURE professor:
KITTLE (8:35 AM) ANDRIANI (11:50 AM) ANDRIANI (2:00 PM)
Circle the alphabet segment of your last name:
A-C D-G H-L M-P R-Z
Chemistry 1210
October 10, 2012
55 minute Exam 2
60 points
Part I. (30 points) Multiple Choice @ 2 pts each. Choose the single best answer.
Write your answer in the space provided (use CAPITAL letters please).
______ 1. Which of the following statements is NOT true about the octet rule? a.
The octet rule deals only with valence electrons. b.
Electrons must completely fill the outermost orbital. c.
All elements must have 8 valence electrons. d.
Atoms tend to combine to achieve a noble gas configuration.
______ 2. C
6
H
16(g)
+ O
2(g)
→ CO
2(g)
+ H
2
O
(g) correctly balanced is: a.
2 C
6
H
16(g)
+ 20O
2(g)
→ 12CO
2(g) b. 3 C
6
H
16(g)
+ 5O
2(g)
→ 6CO
2(g)
+ 16H
2
O
(g)
+ 24H
2
O
(g) c. C
6
H
16(g)
+ 10O
2(g)
→ 6CO
2(g)
+ 8H
2
O
(g) d.
1 C
6
H
16(g)
+ 5O
2(g)
→ 3CO
2(g)
+ 4H
2
O
(g)
______ 3. How many moles of fluoride are in 3.15 grams of carbon tetrafluoride? a. 76.0 b. 0.0358 c. 59.9 d. 0.143
______ 4. How many atoms are in 5.13 moles of scandium? a. 3.09×10 24 b. 4.13×10 23 c. 8.52×10 -24 d. 6.02×10 23
______ 5. The family with the generic configuration of s
2
on the periodic table is: a. halogens c. alkali metals b. alkaline Earth metals d. noble gases
4

______6. Which of the following has the largest radius: a. Ba b. Zr c. Al d. F
______ 7. What is the percent mass of fluorine in carbon tetrafluoride? a. 86.35% b. 21.59% c. 25.00% d. 13.65%
______ 8. What is the average atomic mass of sulfur? a. 31.97 b. 32.97 c. 32.06 d. 35.97
______ 9. What is the molar mass of CO
2
? a. 12.01 g/mol b. 28.01 g/mol c. 44.01 g/mol d. 42.01 g/mol
______ 10. Which of the following are TRUE statements? a.
Covalent molecules share electrons on the outside of atoms. b.
Less electronegative elements are placed first when naming compounds. c.
Ionic compounds have a net charge of zero. d.
All of the above.
______ 11. Neon has three stable isotopes, Neon-20, Neon-21, and Neon-22 with masses of 19.992 amu, 20.994 amu, and 21.991 amu, respectively.
Calculate the average atomic mass of Neon given
20
Ne=90.48%,
21
Ne=0.27%,
22
Ne=9.25% a. 20.180 amu b. 6.7265 amu c. 20.992 amu d. 62.997 amu
_______12. Polarity can be determined by all of the following except: a.
Symmetry b.
Atom Polarity
b. Electronegativity Values
d. Net Dipole Values
________13. How many resonance structures are possible for Ozone (O
3
)? a.
1 b. 2 c. 3 d. 4
________14. How many valence electrons does silicon have? a.
2 b.3 c. 4 d. 6
5

Part II . (40 pts) Short answer. Please answer each question fully.
1. (8 pts) Draw the Lewis Dot Structures for the following molecules: a.
As
2
O b.
PO
4
3-
2. Complete the following table for the compounds drawn in question number one.
Compound # lone pairs # bonds
As
2
O
Shape Angle Polar / Non-Polar
PO
4
3-
3. (4 pts) Balancing Equations. Balance the following chemical equation.
_____C
3
H
7(g)
+ _____O
2(g)
→ _____CO
2(g)
+ _____H
2
O
(l)
4. (16 pts) Nomenclature. Use your periodic table for reference. Complete the following table. No partial credit.
Chemical Formula
Fe
2
O
3
MgF
2
Systematic Name
LiH
2
PO
4
NO
3
6

Chemical Formula Systematic Name
Lead (II) Oxide
Calcium Bisulfate
Rubidium Hydroxide
Bromine Heptanitride
5.
(9 pts) Write the noble gas configuration for the following:
Chemical Formula Noble Gas Configuration
Ag
4+
Sb
3-
Ti
Part III.
(20 points) Calculations
1. Balance the following equation a.
(4 points) S
8
reacts with oxygen gas to produce sulfur dioxide. Write and balance the described equation above. b.
(4 points) Using the balanced equation above, calculate the number of
moles of O
2
that react with 3 moles of S
8
7

c.
(6 points) How many grams of O
2
are needed to react with 347 grams of
S
8
? d.
(6 points) How many grams of SO
2
are produced by 347 grams of S
8
(assuming an excess of oxygen)?
8