Test bank for General Chemistry - Atoms First, 2nd Edition - Mcmurry.

General Chemistry: Atoms First
Chapter 6 Chemical Arithmetic: Stoichiometry

6.1 Multiple Choice Questions

1) Which one of the following statements about balanced equations is false? In a balanced
reaction
A) atoms must be balanced on both sides of the reaction arrow.
B) mass must be conserved.
C) molecules must be balanced on both sides of the reaction arrow.
D) net charge must be balanced on both sides of the reaction
arrow. Answer: C
Diff: 1
Topic: Section 6.2 Balancing Chemical Equations

2) Which one of the following statements about balanced equations is true? A reaction is
balanced by
A) changing the charge on an ion.
B) changing the formula of the molecule.
C) multiplying by suitable coefficients.
D) rearranging atoms in a
molecule. Answer: C
Diff: 1
Topic: Section 6.2 Balancing Chemical Equations

3) What is the stoichiometric coefficient for oxygen when the following equation is
balanced using the lowest, whole-number coefficients
C3H8O(l) + O2(g) → CO2(g) + H2O(l)
A) 3
B) 5
C) 7
D) 9
Answer: D
Diff: 2
Topic: Section 6.2 Balancing Chemical
Equations Algo. Option: algorithmic

,4) What is the sum of the coefficients when the following equation is balanced using the
lowest, whole numbered coefficients?
PH3(g) + O2(g) → P4O10(s) + H2O(g)
A) 10
B) 12
C) 19
D) 22
Answer: C
Diff: 2
Topic: Section 6.2 Balancing Chemical Equations

5) What is the sum of the coefficients when the following equation is balanced using the
lowest, whole numbered coefficients?
B2O3(s) + HF(l) → BF3(g) + H2O(l)
A) 8
B) 11
C) 15
D) none of these
Answer: D
Diff: 2
Topic: Section 6.2 Balancing Chemical Equations

6) Aluminum metal reacts with iron(II) sulfide to form aluminum sulfide and iron metal. What is
the stoichiometric coefficient for aluminum when the chemical equation is balanced using the
lowest, whole-number stoichiometric coefficients?
A) 1
B) 2
C) 3
D) 4
Answer: B
Diff: 3
Topic: Section 6.2 Balancing Chemical
Equations Algo. Option: algorithmic

7) Calcium phosphate reacts with sulfuric acid to form calcium sulfate and phosphoric acid.
What is the stoichiometric coefficient for sulfuric acid when the chemical equation is
balanced using the lowest, whole-number stoichiometric coefficients?
A) 1
B) 2
C) 3
D) none of these
Answer: C
Diff: 3
Topic: Section 6.1 Chemical Symbols on Different
Levels Algo. Option: algorithmic

,8) Given the chemical equation: N2 + 3 H2 → 2 NH3. On a microscopic level, what do
the coefficients mean?
A) 1 atom of nitrogen reacts with 3 atoms of hydrogen to give 2 atoms of ammonia.
B) 28 g of nitrogen reacts with 6 grams of hydrogen to give 34 grams of ammonia.
C) 1 mole of nitrogen reacts with 3 moles of hydrogen to give 2 moles of ammonia.
D) 1 molecule of nitrogen reacts with 3 molecules of hydrogen to give 2 molecules of
ammonia. Answer: D
Diff: 1
Topic: Section 6.1 Chemical Symbols on Different Levels

9) Given the chemical equation: N2 + 3 H2 → 2 NH3. On a macroscopic level, what do
the coefficients mean?
A) 1 atom of nitrogen reacts with 3 atoms of hydrogen to give 2 atoms of ammonia.
B) 1 mole of nitrogen reacts with 3 moles of hydrogen to give 2 moles of ammonia.
C) 1 molecule of nitrogen reacts with 3 molecules of hydrogen to give 2 molecules of ammonia.
D) all of the above
Answer: B
Diff: 1
Topic: Section 6.1 Chemical Symbols on Different Levels

10) 1.00 mole of O2 contains the same number of molecules as
A) 0.667 mole of O3.
B) 1.00 mole of CH3CO2H.
C) 2.00 mole of CH3CH2OH.
D) all of the
above. Answer: B
Diff: 1
Topic: Section 6.3 Stoichiometry: The Arithmetic of Chemical Reactions

11) 1.00 mole of O2 contains the same number of oxygen atoms as
A) 0.667 mole of O3.
B) 1.00 mole of CH3CO2H.
C) 2.00 mole of CH3CH2OH.
D) all of the
above. Answer: D
Diff: 2
Topic: Section 6.3 Stoichiometry: The Arithmetic of Chemical Reactions

, 12) What is the mass of an atom of the element hydrogen?
A) 2.0 g
B) 1.0 g
C) 3.4 × 10–24 g
D) 1.7 × 10–24 g
Answer: D
Diff: 2
Topic: Section 6.3 Stoichiometry: The Arithmetic of Chemical Reactions

13) What is the molar mass of aspartic acid, C4O4H7N?
A) 43 g/mol
B) 70 g/mol
C) 133 g/mol
D) 197
g/mol
Answer: C
Diff: 2
Topic: Section 6.2 Balancing Chemical Equations

14) What is the molar mass of Co(NO3)2?
A) 90 g/mol
B) 121 g/mol
C) 152 g/mol
D) 183
g/mol
Answer: D
Diff: 2
Topic: Section 6.2 Balancing Chemical Equations

15) What is the molar mass of calcium permanganate?
A) 159 g/mol
B) 199 g/mol
C) 216 g/mol
D) 278
g/mol
Answer: D
Diff: 3
Topic: Section 6.2 Balancing Chemical Equations

16) What is the molar mass of hydrogen gas?
A) 1.00 g/mol
B) 2.00 g/mol
C) 6.02 × 1023 g/mol
D) 1.20 × 1023 g/mol
Answer: B
Diff: 2
Topic: Section 6.2 Balancing Chemical