Name:______KEY_____________
Exam 2 – CHEM&139 – Spring 2009 – Chapters 5,6, & 9 – 100 Points
1. __T__T/F Ionic compounds contain metals and nonmetals. (4 points)
2. __T__T/F Covalent compounds share electrons. (4 points)
3. A sulfide ion has _______extra electrons. (3 points)
a. 2
b. 4
c. 7
d. 8
4. Identify the ions present in CsC2H3O2. (3 points)
a. CsC2H3O2 is not ionic.
b. Cs+2 & C2H3O2-2
c. C2-4, H-3, & O2-2
d. None of the above
5. Which of the following formulas is not correct? (3 points)
a. GeI4
b. Ag2PO3
c. Fe2O3
d. Ca(OH)2
e. In(CN)3
6. What is the charge on P in PO4-3? (3 points)
a. 0
b. 1
c. 3
d. 5
7. What is the molar mass of ammonium permanganate? (5 points)
a. 136.97 g/mol
b. 154.98 g/mol
c. 255.91 g/mol
d. None of the above
________/25 points total
CHEM&139 EXAM2 SPRING2009
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8. How many grams are in 2.09 mol hydrogen gas? (5 points)
2.09mol 
2.0159 g
 4.21g
1mol
9. What is the mass percent of nitrogen in cobalt (III) nitrite? (5 points)
Co( NO2 )3
42.0201
100  21.3354%
196.950
10. A 0.77 mg sample of nitrogen reacts with chlorine to form 6.61 mg of the
chloride. What is the empirical formula of the nitrogen chloride? (8 points)
1g
1mol

 5.5  105 molN
1000mg 14.0067 g
1g
1mol
5.84mg 

 1.6 104 molCl
1000mg 35.4527 g
0.77 mg 
5.5 105 mol  5.5 105 mol  1.0 N
1.6 104 mol  5.5 105 mol  3.0Cl
NCl3
11. Name the following compounds/state their chemical formulae: (2 points each – 24
points total)
a. Silver perchlorate
AgClO4
b. Molybdenum (II) arsenide
c. P2O5
diphosphorous pentoxide
d. Boron trihydride
e. BaCO3
Mo3As2
BH3
barium carbonate
________/28 points total
CHEM&139 EXAM2 SPRING2009
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f. NiCl2 nickel (II) chloride
g. Phosphorous acid
H3PO3(aq)
h. HCN(aq)
hydrocyanic acid
i. Bi(MnO4)5
bismuth (V) permanganate
j. TiO2
titanium (IV) oxide
k. SiO2
silicon dioxide
l. Sulfur trioxide
SO3
12. Give the short-hand electron configurations for the following species: (3 points
each – 15 points total)
a. Al
[Ne]3s23p1
b. Br[Kr]
c. Y3+
[Kr]
d. Ag
[Kr]5s14d10
e. Cr
[Ar]4s13d5
13. Balance the following equations: (4 points each – 8 points total)
a. _1__Fe2O3(s) + __3_H2SO4(aq) __1_Fe2(SO4)3(aq) + _3_H2O(l)
b. _2__C20H42(g) + _61__O2(g)  __40_CO2(g) + _42_H2O(l)
________/37 points total
CHEM&139 EXAM2 SPRING2009
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14. Calculate the empirical and molecular formulae of acetaminophen (Tylenol),
given: C, 63.56%; H, 6.00%; N, 9.27%; O, 21.17% and a molecular mass of
151.169 g/mol. (10 points)
1mol
 5.292mol  0.662mol  7.990  8C
12.011g
1mol
6.00 gH 
 5.95mol  0.662mol  8.99  9 H
1.00794 g
1mol
9.27 gN 
 0.662mol  0.662mol  1.00  1N
14.0067 g
1mol
21.17 gO 
 1.323mol  0.662mol  1.998  2O
15.9994 g
emp for  C8 H 9 NO2  151.165 g / mol
63.56 gC 
151.169 g / mol
1
151.165 g / mol
molecular formula  (C8 H 9 NO2 )1  C8 H 9 NO2
n
________/10 points total
CHEM&139 EXAM2 SPRING2009
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