CHEM 1411- Quiz 3
NAME:
1. Indicate which set of coefficients balances the equation
________NH3 + ________O2  ________NO + ________H2O
A) 3, 2, 1, 3
B) 6, 5, 4, 4
C) 2, 6, 3, 2
D) 4, 5, 4, 6
E) 3, 2, 2, 3
2. When the following reaction is balanced the coefficient in front of carbon dioxide is:
____ C5H12 + ____ O2  ____ CO2 + ____ H2O
A) 5
B) 6
C) 7
D) 10
E) 12
3. Which one of the following conversion factors is not consistent with the equation?
4NH3 +5 O2  4NO + 6H2O
A)
5 moles O2
6 moles H 2 O
B)
4 moles NO
4 moles NH3
C)
4 moles NH3
5 moles H 2 O
D)
4 moles NO
5 moles O2
4. Given the following equation, 2 N2 + 5 O2 → 2 N2O5, 1.25 moles of nitrogen requires _____ moles
of oxygen.
A) 0.500
B) 1.75
C) 3.13
D) 1.56
E) 1.25
5. Which of the following is the correct “set-up” for the problem “How many grams of H2O will be
produced from 3.2 moles of O2 and an excess of H2S” according to the reaction
2H2
2
 2H2
2
A) 3.2 moles O2 
18.02 g H2 O
2 moles H2 O
B) 3.2 moles O2 
32.00 g O2 18.02 g H2 O

1 mole O2
32.00 g O2
C) 3.2 moles O2 
2 moles H 2 O 18.02 g H 2 O

3 moles O2
1 mole H 2 O
D) 3.2 moles O2 
32.00 g O2 2 moles H 2 O

1 mole O2
3 moles O2
6. How many Cl atoms are present in 2.16 moles of NCl3?
A) 2.4  1022 Cl atoms
B) 8.4  1024 Cl atoms
C) 3.90  1024 Cl atoms
D) 6.6  1026 Cl atoms
E) 4.33  1023 Cl atoms
7.
What is the formula weight of Ba(C2H3O2)2 in grams per mole?
A) 392.71
B) 255.43
C) 196.38
D) 306.42
E) 164.86
8.
The mass percentage of Cl in the compound KClO3 is ________.
A) 53.87%
B) 64.19%
C) 33.33%
D) 36.51%
E) 28.93%
9. A 2.00 g sample of cholesterol contains 1.68 g C, 0.24 g H, and 0.080 g O. What is the percent
composition of C in cholesterol?
A) 76%
B) 91%
C) 84%
D) 56%
E) 4.0%
10. Calculate the number of lithium atoms in 3.66 moles of lithium.
A) 1.60  1023
B) 6.23  1025
C) 3.54  1025
D) 8.97  1026
E) 2.20  1024
11. Sulfur trioxide, SO3, is made from the oxidation of SO2, and the reaction is represented
by the equation
2SO2 + O2 → 2SO3
A 25-g sample of SO2 gives 18 g of SO3. The percent yield of SO3 is .
A) 31%
B) 9%
C) 14%
D) 58%
E) 100%
12. Ammonia, NH3, and oxygen can be reacted together in the presence of a catalyst to form
only nitrogen monoxide and water. The number of moles of oxygen consumed for every
7.00 mol of NO produced is .
A) 4.38
B) 8.75
C) 17.5
D) 26.3
E) 35.0
13. An atom of an element weighs 5.40 × 10-23 g. What is the atomic mass of this element in
atomic mass units?
A) 27.5 amu
B) 28.6 amu
C) 29.7 amu
D) 31.3 amu
E) 32.5 amu
14. C3H8 + 5O2 → 3CO2 + 4H2O
How many grams of oxygen are required to burn 6.2 g of C3H8?
A) 4.5 g
B) 69 g
C) 39 g
D) 23 g
E) 56 g
15. A sample containing only carbon, hydrogen, phosphorus, and oxygen is subjected to
elemental analysis. After complete combustion, a 0.6820-g sample of the compound
yields 0.9779 g of CO2, 0.6005 g of H2O, and 0.5257 g of P4O10. What is the empirical
formula of the compound?
A) C3H9PO
B) CH2P4O13
C) CH3PO
D) C2H6P2O4
E) C2H3PO
16. How many moles of silver are contained in 8.00 kg of silver?
A) 74.1 × 10-3 mol
B) 74.1 × 10-1 mol
C) 74.1 mol
D) 74.1 × 101 mol
E) 74.1 × 103 mol
17. What is the mass in grams of one molecule of the compound C9H6O4?
A) 3.38 × 1021 g
B) 178 g
C) 2.96 × 10-22 g
D) 3.16 × 10-22 g
E) 1.53 × 10-22 g
18. How many moles of hexachlorobenzene, C6Cl6, are there in 2.55 g of C6Cl6?
A) 0.00895 mol
B) 0.0119 mol
C) 0.0185 mol
D) 0.0354 mol
E) 7.27 × 102 mol
19. A crystal of the mineral troegerite, (UO2)3(AsO4)2 ● 12H2O (FM = 1304 amu), contains
____% uranium by mass.
A) 18.2
B) 31.2
C) 43.8
D) 62.5
E) 54.8
20. If 49.6 g of O2 is mixed with 49.6 g of H2 and the mixture is ignited, what is the
maximum mass of water that may be produced?
A) 49.6 g
B) 55.8 g
C) 88.2 g
D) 446 g
E) 99 g