Chapter 19
Standardized Test Preparation
Preview
• Multiple Choice
• Short Answer
• Extended Response
Chapter 19
Standardized Test Preparation
Multiple Choice
1. In the following reaction, which species is
reduced?
2K + Br2  2K + + 2Br –
A. K
B. Br2
C. All of the above
D. None of the above
Chapter 19
Standardized Test Preparation
Multiple Choice
1. In the following reaction, which species is
reduced?
2K + Br2  2K + + 2Br –
A. K
B. Br2
C. All of the above
D. None of the above
Chapter 19
Standardized Test Preparation
Multiple Choice
2. The oxidation number of the sulfur atom in the
SO24– ion is
A.
B.
C.
D.
+2.
−2.
+6.
+4.
Chapter 19
Standardized Test Preparation
Multiple Choice
2. The oxidation number of the sulfur atom in the
SO24– ion is
A.
B.
C.
D.
+2.
−2.
+6.
+4.
Chapter 19
Standardized Test Preparation
Multiple Choice
3. A half-reaction
A. involves a change in the oxidation state of
an element.
B. always contains H2O molecules.
C. always contains H+ ions.
D. All of the above
Chapter 19
Standardized Test Preparation
Multiple Choice
3. A half-reaction
A. involves a change in the oxidation state of
an element.
B. always contains H2O molecules.
C. always contains H+ ions.
D. All of the above
Chapter 19
Standardized Test Preparation
Multiple Choice
4. In the following reaction, which is the oxidizing
agent?
AgNO2 + Cl2 + 2KOH  AgNO3 + 2KCl + H2O
A.
B.
C.
D.
AgNO2
Cl2
KOH
KCl
Chapter 19
Standardized Test Preparation
Multiple Choice
4. In the following reaction, which is the oxidizing
agent?
AgNO2 + Cl2 + 2KOH  AgNO3 + 2KCl + H2O
A.
B.
C.
D.
AgNO2
Cl2
KOH
KCl
Chapter 19
Standardized Test Preparation
Multiple Choice
5. What are the oxidation states (in increasing order)
of the element that undergoes disproportionation in
the following reaction:
Cl2 + H2O  HCl + HOCl
A.
B.
C.
D.
−1, 0, +2
−1, 0, +1
−2, −1, 0
None of the above
Chapter 19
Standardized Test Preparation
Multiple Choice
5. What are the oxidation states (in increasing order)
of the element that undergoes disproportionation in
the following reaction:
Cl2 + H2O  HCl + HOCl
A.
B.
C.
D.
−1, 0, +2
−1, 0, +1
−2, −1, 0
None of the above
Chapter 19
Standardized Test Preparation
Multiple Choice
6. Which reaction is a redox reaction?
A. Al2O3 + 6HCl  2AlCl3 + 3H2O
B. 2HCO3–  CO2 + CO32– + H2O
C. SiBr4 + 3H2O  H2SiO3 + 4HBr
D. H2O + PbO2 + NaOH + KCl  KClO + NaPb(OH)3
Chapter 19
Standardized Test Preparation
Multiple Choice
6. Which reaction is a redox reaction?
A. Al2O3 + 6HCl  2AlCl3 + 3H2O
B. 2HCO3–  CO2 + CO32– + H2O
C. SiBr4 + 3H2O  H2SiO3 + 4HBr
D. H2O + PbO2 + NaOH + KCl  KClO + NaPb(OH)3
Chapter 19
Standardized Test Preparation
Multiple Choice
7. Arrange the following in order of increasing
oxidation number of the sulfur atom:
S2O32– , S4O62– , HSO4– , and H2S.
2–
2–
–
A. H2S, S2O3 , S 4O6 , HSO4
B. S2O32– , H2S, S4O62– , HSO4–
C. H2S, S2O32– , HSO4– , S 4O62–
–
2–
2–
D. HSO4 , S2O3 , S4O6 , H2S
Chapter 19
Standardized Test Preparation
Multiple Choice
7. Arrange the following in order of increasing
oxidation number of the sulfur atom:
S2O32– , S4O62– , HSO4– , and H2S.
2–
2–
–
A. H2S, S2O3 , S 4O6 , HSO4
B. S2O32– , H2S, S4O62– , HSO4–
C. H2S, S2O32– , HSO4– , S 4O62–
–
2–
2–
D. HSO4 , S2O3 , S4O6 , H2S
Chapter 19
Standardized Test Preparation
Multiple Choice
8. Which answer contains the correct information about
the following reaction:
2Pb(NO3 )2  2PbO + 4NO2 + O2
A. This reaction is a decomposition reaction
and not a redox reaction.
B. This reaction is a redox reaction in which the lead
is reduced and the oxygen is oxidized.
C. This reaction is a disproportionation reaction.
D. This reaction is a redox reaction in which the
nitrogen is reduced and the oxygen is oxidized.
Chapter 19
Standardized Test Preparation
Multiple Choice
8. Which answer contains the correct information about
the following reaction:
2Pb(NO3 )2  2PbO + 4NO2 + O2
A. This reaction is a decomposition reaction
and not a redox reaction.
B. This reaction is a redox reaction in which the lead
is reduced and the oxygen is oxidized.
C. This reaction is a disproportionation reaction.
D. This reaction is a redox reaction in which the
nitrogen is reduced and the oxygen is oxidized.
Chapter 19
Standardized Test Preparation
Short Answer
9. Determine the oxidation numbers for Cu in the
superconductor YBa2Cu3O7.Yttrium (Y) has an
oxidation number of +3. (Cu does not have
oxidation numbers greater than +3.) Give only
integer oxidation numbers.
Chapter 19
Standardized Test Preparation
Short Answer
9. Determine the oxidation numbers for Cu in the
superconductor YBa2Cu3O7.Yttrium (Y) has an
oxidation number of +3. (Cu does not have
oxidation numbers greater than +3.) Give only
integer oxidation numbers.
Answer: The oxidation numbers for Y, Ba, and O are
+3, +2, and −2, respectively. Therefore, the sum
of the oxidation numbers for the three Cu atoms
must be +7. Two Cu atoms must have +2
oxidation states, and one Cu atom must have a
+3 oxidation state.
Chapter 19
Standardized Test Preparation
Short Answer
10. What is an oxidizing agent?
Chapter 19
Standardized Test Preparation
Short Answer
10. What is an oxidizing agent?
Answer: An oxidizing agent is a species that
causes another species to be oxidized in a
redox reaction. An oxidizing agent is therefore
reduced in a redox reaction.
Chapter 19
Standardized Test Preparation
Extended Response
11. B, F, K, and L are four unknown reducing agents
that oxidize to singly charged cations. Using the
following information, construct a table showing
the relative strengths of the oxidizing and reducing
agents. Data: F reduces K+, B+, and L+. B+
oxidizes K and F, but not L.
Chapter 19
Standardized Test Preparation
Extended Response
11.
B, F, K, and L are four unknown reducing agents that oxidize
to singly charged cations. Using the following information,
construct a table showing the relative strengths of the
oxidizing and reducing agents. Data: F reduces K+, B+, and
L+. B+ oxidizes K and F, but not L.
Answer:
Reducing
agents
F
K
B
L
Oxidizing
agents
F+
K+
B+
L+
Chapter 19
Standardized Test Preparation
Extended Response
12. Balance the equation for the following reaction
in basic solution:
ClO2  KClO3 + KClO2
Give the balanced equation for each halfreaction and for the overall reaction. Give the
oxidizing agent and the reducing agent.
Chapter 19
Standardized Test Preparation
Extended Response
12. Balance the equation for the following reaction in basic
solution:
ClO2  KClO3 + KClO2
Give the balanced equation for each half-reaction and for the
overall reaction. Give the oxidizing agent and the reducing
agent.
Answer:
Oxidation half-reaction: 2OH– + ClO2  ClO3– + e – + H2O
–
–
Reduction half-reaction: ClO2 + e  ClO2
Overall reaction: 2ClO2 + 2KOH  KClO3 + KClO2 + H2O
This reaction is a disproportionation reaction; therefore, ClO2 is
both the reducing agent and the oxidizing agent.