Exam
Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) When the following equation is balanced, the coefficients are
__________.
C
8
H
18
+ O
2
→ CO
2
+ H
2
O
1) ______
A) 2, 25, 16, 18
B) 1, 4, 8, 9
C) 2, 12, 8, 9
D) 2, 3, 4, 4
E) 4, 4, 32, 36
2) Of the reactions below, which one is not a combination reaction?
A) CaO + H
2
O → Ca(OH)
2
B) C + O
2
→ CO
2
C) 2Mg + O
2
→ 2MgO
D) 2N
2
+ 3H
2
→ 2NH
3
E) 2CH
4
+ 4O
2
→ 2CO
2
+ 4H
2
O
3) Of the reactions below, which one is a decomposition reaction?
A) 2CH
4
+ 4O
2
→ 2CO
2
+ 4H
2
O
B) 2Mg + O
2
→ 2MgO
C) NH
4
Cl → NH
3
+ HCl
D) 2N
2
+ 3H
2
→ 2NH
3
E) Cd(NO
3
)
2
+ Na
2
S → CdS + 2NaNO
3
4) Which one of the following substances is the product of this combination reaction?
Al (s) + I
2
(s) → __________
A) Al
3
I
2
B) AlI
2
C) Al
2
I
3
D) AlI
E) AlI
3
2) ______
3) ______
4) ______

5) Which of the following are combination reactions?
1) CH
4
(g) + O
2
(g) → CO
2
(g) + H
2
O (l)
2) CaO (s) + CO
2
(g) → CaCO
3
(s)
3) Mg (s) + O
2
(g) → MgO (s)
4) PbCO
3
(s) → PbO (s) + CO
2
(g)
A) 2, 3, and 4
B) 1, 2, and 3
C) 1, 2, 3, and 4
D) 2 and 3
E) 4 only
6) Which of the following are decomposition reactions?
1) CH
4
(g) + O
2
(g) → CO
2
(g) + H
2
O (l)
2) CaO (s) + CO
2
(g) → CaCO
3
(s)
3) Mg (s) + O
2
(g) → MgO (s)
4) PbCO
3
(s) → PbO (s) + CO
2
(g)
5) ______
6) ______
A) 1, 2, 3, and 4
B) 1, 2, and 3
C) 2 and 3
D) 2, 3, and 4
E) 4 only
7) The formula of nitrobenzene is C
6
H
5
NO
2
. The molecular weight of this 7) ______ compound is __________ amu.
A) 3.06
B) 123.11
C) 43.03
D) 109.10
E) 107.11
8) The formula weight of potassium dichromate (K
2
Cr
2
O
7
) is __________ amu.
8) ______
A) 294.18
B) 107.09
C) 255.08
D) 242.18
E) 333.08
9) ______

9) The formula weight of potassium phosphate (K
3
PO
4
) is __________ amu.
A) 86.07
B) 251.37
C) 173.17
D) 196.27
E) 212.27
10) What is the mass % of carbon in dimethylsulfoxide (C
2
H
6
SO) rounded 10) ______ to three significant figures?
A) 20.6
B) 79.8
C) 30.7
D) 7.74
E) 60.0
11) The mass % of Al in aluminum sulfate (Al
2
(SO
4
)
3
) is __________.
A) 7.886
B) 15.77
C) 35.94
D) 21.93
E) 45.70
12) The mass % of C in methane (CH
4
) is __________.
11) ______
12) ______
A) 25.13
B) 7.743
C) 74.87
D) 92.26
E) 133.6
13) The formula weight of calcium nitrate (Ca(NO
3
)
2
), rounded to one decimal place, is __________ amu.
A) 204.2
B) 102.1
C) 116.1
D) 150.1
E) 164.0
13) ______
14) ______

14) Calculate the percentage by mass of nitrogen in Pb(NO
3
)
2
.
A) 4.2
B) 12.6
C) 5.2
D) 8.5
E) 10.4
15) How many molecules of CH
4
are in 48.2 g of this compound?
A) 2.90 × 10 25
15) ______
B) 4.00
C) 1.81 × 10 24
D) 3.00
E) 5.00 × 10 24
16) A 30.5 gram sample of glucose (C
6
H
12
O
6
) contains __________ atoms of 16) ______ carbon.
A) 2.04 x 10 23
B) 6.12 x 10 23
C) 1.02 x 10 23
D) 1.22 x 10 24
E) 6.02 x 10 23
17) How many moles of pyridine (C
5
H
5
N) are contained in 3.13 g of pyridine?
A) 25.3
B) 0.00404
C) 0.319
D) 0.0396
E) 4.04 × 10 3
18) The molecular formula of aspartame, the generic name of
17) ______
18) ______
NutraSweet ® , is The molar mass of aspartame, rounded to the nearest integer, is __________ g.
A) 294
B) 43
C) 156
D) 39
E) 24

19) A nitrogen oxide is 63.65% by mass nitrogen. The molecular formula could be __________.
19) ______
A) N
2
O
4
B) NO
C) N
2
O
D) NO
2
E) either NO
2
or N
2
O
4
20) Which hydrocarbon pair below have identical mass percentage of C?
20) ______
A) C
2
H
4
and C
3
H
6
B) C
2
H
4
and C
4
H
2
C) C
2
H
4
and C
3
H
4
D) C
3
H
4
and C
3
H
6
E) none of the above
21) Sulfur and oxygen react to produce sulfur trioxide. In a particular experiment, 7.9 grams of SO
3
are produced by the reaction of 5.0 grams of O
2
with 6.0 grams of S. What is the % yield of SO
3
in this experiment?
S (s) + O
2
(g) → SO
3
(g) (not balanced)
21) ______
A) 63
B) 95
C) 75
D) 32
E) 99
22) The balanced molecular equation for complete neutralization of H
2
SO
4
22) ______ by KOH in aqueous solution is __________.
A) 2H + (aq) + 2KOH (aq) → 2H
2
O (l) + 2K + (aq)
B) H
2
SO
4
(aq) + 2KOH (aq) → 2H
2
O (l) + K
2
SO
4
(aq)
C) H
2
SO
4
(aq) + 2KOH (aq) → 2H
2
O (l) + K
2
SO
4
(s)
D) 2H + (aq) + 2OH (aq) → 2H
2
O (l)
E) H
2
SO
4
(aq) + 2OH (aq) → 2H
2
O (l) + SO
42-
(aq)
23) ______

23) Aqueous potassium chloride will react with which one of the following in an exchange (metathesis) reaction?
A) sodium chloride
B) calcium nitrate
C) sodium bromide
D) barium nitrate
E) lead nitrate
24) The net ionic equation for formation of an aqueous solution of NiI
2 accompanied by evolution of CO
2
gas via mixing solid NiCO
3
and aqueous hydriodic acid is __________.
A) NiCO
3
(s) + 2HI (aq) → 2H
2
O (l) + CO
2
(g) + NiI
2
(aq)
B) NiCO
3
(s) + I (aq) → 2H
2
O (l) + CO
2
(g) + Ni 2+ (aq) + HI (aq)
C) NiCO
3
(s) + 2HI (aq) → H
2
O (l) + CO
2
(g) + Ni 2+ (aq) + 2I (aq)
D) 2NiCO
3
(s) + HI (aq) → 2H
2
O (l) + CO
2
(g) + 2Ni 2+ (aq)
E) NiCO
3
(s) + 2H + (aq) → H
2
O (l) + CO
2
(g) + Ni 2+ (aq)
25) An aliquot (28.7 mL) of a KOH solution required 31.3 mL of 0.118 M
HCl for neutralization. What mass (g) of KOH was in the original sample?
A) 7.28
B) 0.414
C) 0.173
D) 0.207
E) 1.64
26) A 36.3 mL aliquot of 0.0529 M H
2
SO
4
(aq) is to be titrated with 0.0411
M NaOH (aq). What volume (mL) of base will it take to reach the equivalence point?
A) 46.7
B) 187
C) 93.4
D) 3.84
E) 1.92
24) ______
25) ______
26) ______
27) ______

27) A 13.8 mL aliquot of 0.176 M H
3
PO
4
(aq) is to be titrated with 0.110 M
NaOH (aq). What volume (mL) of base will it take to reach the equivalence point?
A) 22.1
B) 20.9
C) 199
D) 7.29
E) 66.2
28) The density of air at STP is 1.285 g/L. Which of the following cannot be used to fill a balloon that will float in air at STP?
A) CH
4
B) NO
C) HF
D) NH
3
E) Ne
28) ______