What is the coefficient of methanol in the balanced equation?
A) 1
B) 2
C) 3
D) 4
E) 3/2
23) Write the balanced equation for the reaction that occurs when methanol, CH3OH (l), is burned in air.
What is the coefficient of oxygen in the balanced equation?
A) 1
B) 2
C) 3
D) 4
E) 3/2
24) What is the coefficient of O2 when the following equation is completed and balanced?
C4H8O2 + O2 → __________
A) 2
B) 3
C) 5
D) 6
E) 1
25) Predict the product in the combination reaction below.
Al (s) + N2 (g) → __________
A) AlN
B) Al3N
C) Al N2
D) Al3N2
E) AlN3
22
26) The balanced equation for the decomposition of sodium azide is __________.
A) 2NaN3 (s) → 2Na (s) + 3 N2 (g)
B) 2NaN3 (s) → Na2 (s) + 3 N2 (g)
C) NaN3 (s) → Na (s) + N2 (g)
D) NaN3 (s) → Na (s) + N2 (g) + N (g)
E) 2NaN3 (s) → 2Na (s) + 2 N2 (g)
27) There are __________ mol of carbon atoms in 4 mol C4H8O2.
A) 4
B) 8
C) 16
D) 20
E) 32
28) There are __________ sulfur atoms in 25 molecules of C4H4S2.
A) 1.5 × 1025
B) 4.8 × 1025
C) 3.0 × 1025
D) 50
E) 6.02 × 1023
29) There are __________ hydrogen atoms in 25 molecules of C4H4S2.
A) 25
B) 3.8 × 1024
C) 6.0 × 1025
D) 100
E) 1.5 × 1025
30) A sample of C3H8O that contains 200 molecules contains __________ carbon atoms.
A) 600
B) 200
C) 3.61 × 1026
D) 1.20 × 1026
E) 4.01 × 1025
31) How many moles of carbon monoxide are there in 36.55 g of carbon monoxide?
23
A) 0.8452
B) 1.305
C) 0.9291
D) 2.589
E) 3.046
32) How many moles of carbon dioxide are there in 52.06 g of carbon dioxide?
A) 0.8452
B) 1.183
C) 6.022 × 1023
D) 8.648 × 1023
E) 3.134 × 1025
33) There are __________ molecules of methane in 0.123 mol of methane (CH4).
A) 5
B) 2.46 × 10-2
C) 2.04 × 10-25
D) 7.40 × 1022
E) 0.615
34) What is the empirical formula of a compound that contains 27.0% S, 13.4% O, and 59.6% Cl by
mass?
A) SOCl
B) SOCl2
C) S2OCl
D) SO2Cl
E) ClSO4
35) What is the empirical formula of a compound that contains 29% Na, 41% S, and 30% O by mass?
A) Na2S2O3
B) NaSO2
C) NaSO
D) NaSO34
E) Na2S2O6
36) What is the empirical formula of a compound that contains 49.4% K, 20.3% S, and 30.3% O by
mass?
A) KSO2
B) KSO3
C) K2SO4
D) K2O3
E) KSO4
37) A compound contains 40.0% C, 6.71% H, and 53.29% O by mass. The molecular weight of the
compound is 60.05 amu. The molecular formula of this compound is __________.
A) C2H4O2
B) C H2O
C) C2H3O4
D) C2H2O4
E) CHO2
38) A compound that is composed of carbon, hydrogen, and oxygen contains 70.6% C, 5.9% H, and
23.5% O by mass. The molecular weight of the compound is 136 amu. What is the molecular formula?
A) C8H8O2
B) C8H4O
C) C4H4O
D) C9H12O
E) C5H6O2
39) A compound that is composed of only carbon and hydrogen contains 85.7% C and 14.3% H by
mass. What is the empirical formula of the compound?
A) CH2
B) C2H4
C) C H42
D) C4H8
E) C86H14
40) A compound that is composed of only carbon and hydrogen contains 80.0% C and 20.0% H by
mass. What is the empirical formula of the compound?
A) C20H60
B) C7H20
C) C H3
D) C2H6
E) CH4
41) A compound contains 38.7% K, 13.9% N, and 47.4% O by mass. What is the empirical formula of
the compound?
A) KNO3
B) K2N2O3
C) KNO2
D) K2NO3
E) K4NO5
42) A compound is composed of only C, H, and O. The combustion of a 0.519-g sample of the
compound yields 1.24 g of CO2 and 0.255 g of H2O. What is the empirical formula of the compound?
A) C6H6O
B) C3H3O
C) CH3O
D) C2H6O5
E) C2H6O2
43) Combustion of a 1.031-g sample of a compound containing only carbon, hydrogen, and oxygen
produced 2.265 g of CO2 and 1.236 g of H2O. What is the empirical formula of the compound?
A) C3H8O
B) C3H5O
C) C6H16O2
D) C3H9O3
E) C3H6O3
44) Combustion of a 0.9835-g sample of a compound containing only carbon, hydrogen, and oxygen
produced 1.900 g of CO2 and 1.070 g of H2O. What is the empirical formula of the compound?
A) C2 H5O
B) C4 H10O2
C) C4 H11O2
D) C4 H10O
E) C2 H5O2
45) The combustion of ammonia in the presence of excess oxygen yields NO2 and H2O:
4 NH3 (g) + 7 O2 (g) → 4 NO2 (g) + 6 H2O (g)
The combustion of 43.9 g of ammonia produces __________ g of NO2.
A) 2.58
B) 178
C) 119
D) 0.954
E) 43.9
46) The combustion of propane (C3H8) in the presence of excess oxygen yields CO2 and H2O:
C3H8 (g) + 5 O2 (g) → 3CO2 (g) + 4 H2O (g)
When 2.5 mol of O2 are consumed in their reaction, __________ mol of CO2 are produced.
A) 1.5
B) 3.0
C) 5.0
D) 6.0
E) 2.5
47) Calcium carbide (CaC2) reacts with water to produce acetylene (C2H2):
CaC2 (s) + 2 H2O (g) → Ca(OH)2 (s) + C2H2 (g)
Production of 13 g of C2H2 requires consumption of __________ g of H2O.
A) 4.5
B) 9.0
C) 18
D) 4.8 × 102
E) 4.8 × 10-2
48) Calcium carbide (CaC2) reacts with water to produce acetylene (C2H2):
CaC2 (s) + 2 H2O (g) → Ca(OH)2 (s) + C2H2 (g)
The complete reaction of 57.4 g of CaC2 requires consumption of __________ g of H2O.
A) 0.895
B) 64.1
C) 32.3
D) 1.79
E) 18.0
49) Under appropriate conditions, nitrogen and hydrogen undergo a combination reaction to yield
ammonia:
N2 (g) + 3 H2 (g) → 2NH3 (g)
A 7.1-g sample of N2 requires __________ g of H2 for complete reaction.
A) 0.51
B) 0.76
C) 1.2
D) 1.5
E) 17.2
50) Under appropriate conditions, nitrogen and hydrogen undergo a combination reaction to yield
ammonia:
N2 (g) + 3 H2 (g) → 2NH3 (g)
A __________ g sample of N2 requires 3.0 g of H2 for complete reaction.
A) 0.51
B) 0.76
C) 1.2
D) 14.0
E) 17.2
51) Lead (II) carbonate decomposes to give lead (II) oxide and carbon dioxide:
PbCO3 (s) → PbO (s) + CO2 (g)
How many grams of lead (II) oxide will be produced by the decomposition of 2.50 g of lead (II)
carbonate?
A) 0.41
B) 2.50
C) 0.00936
D) 2.09
E) 2.61
52) The combustion of propane (C3H8) produces CO2 and H2O:
C3H8 (g) + 5 O2 (g) → 3CO2 (g) + 4 H2O (g)
The reaction of 2.5 mol of O2 with 4.6 mol of C3H8 will produce __________ mol of H2O.
A) 4.0
B) 3.0
C) 2.5
D) 2.0
E) 1.0
53) GeF3H is formed from GeH4 and GeF4 in the combination reaction:
GeH4 + 3Ge F4 → 4GeF3H
If the reaction yield is 92.6%, how many moles of GeF4 are needed to produce 8.00 mol of GeF3H?
A) 3.24
B) 5.56
C) 6.48
D) 2.78
E) 2.16
54) Under appropriate conditions, nitrogen and hydrogen undergo a combination reaction to yield
ammonia:
N2 (g) + 3 H2 (g) → 2NH3 (g)
If the reaction yield is 87.5%, how many moles of N2 are needed to produce 3.00 mol of NH3?.
A) 0.166
B) 1.00
C) 1.5
D) 1.71
E) 2.32
55) Lead (II) carbonate decomposes to give lead (II) oxide and carbon dioxide:
PbCO3 (s) → PbO (s) + CO2 (g)
If the reaction yield is 95.7%, how many grams of lead (II) oxide will be produced by the decomposition
of 2.50 g of lead (II) carbonate?
A) 1.04
B) 1.55
C) 2.09
D) 4.00
E) 5.55
56) The combustion of ammonia in the presence of oxygen yields NO2 and H2O:
4 NH3 (g) + 7 O2 (g) → 4 NO2 (g) + 6 H2O (g)
The combustion of 43.9 g of ammonia with 258 g of oxygen produces __________ g of NO2.
A) 212
B) 178
C) 119
D) 0.954
E) 43.9
57) What mass in grams of hydrogen is produced by the reaction of 4.73 g of magnesium with 1.83 g of
water?
Mg (s) + 2 H2O (l) → Mg(OH)2 (s) + H2 (g)
A) 0.102
B) 0.0162
C) 0.0485
D) 0.219
E) 0.204
58) If the reaction yield is 94.4%, what mass in grams of hydrogen is produced by the reaction of 4.73 g
of magnesium with 1.83 g of water?
Mg (s) + 2 H2O (l) → Mg(OH)2 (s) + H2 (g)
A) 0.0962
B) 0.0162
C) 0.0485
D) 0.219
E) 0.204
59) Silver nitrate and aluminum chloride react with each other by exchanging anions:
3AgNO3 (aq)+ AlCl3 (aq) → Al(NO3)3 (aq) + 3AgCl (s)
What mass in grams of AgCl is produced when 4.22 g of AgNO3 react with 7.73 g of AlCl3?
A) 17.6
B) 4.22
C) 24.9
D) 3.56
E) 11.9
60) How many moles of magnesium oxide are produced by the reaction of 3.82 g of magnesium nitride
with 7.73 g of water?
Mg3N2 + 3 H2O → 2NH3 + 3MgO
A) 0.114
B) 0.0378
C) 0.429
D) 0.0756
E) 4.57
61) A 3.82-g sample of magnesium nitride is reacted with 7.73 g of water.
Mg3N2 + 3 H2O → 2NH3 + 3MgO
The yield of MgO is 3.60 g. What is the percent yield in the reaction?
A) 94.5
B) 78.4
C) 46.6
D) 49.4
E) 99.9