Multiple Choice
Identify the choice that best completes the statement or answers
the question.
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1.
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Which of the following is the INCORRECT
statement?
a. | The oxidation number of chlorine atoms in Cl2
is zero. | b. | Oxidation results in an increase in oxidation
number. | c. | The oxidizing agent in a redox reaction is
reduced. | d. | Electrons are being transferred in a redox
reaction. | e. | Reduction is a loss of
electrons. |
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2.
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Which substance is being oxidized in the following
reaction?
2 HCl(aq) + Zn(s) ® ZnCl2(aq) +
H2(g)
a. | H+(aq) ions | b. | Cl-(aq) ions | c. | Zn
(s) | d. | Zn2+(aq) ions | e. | H2(g) |
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3.
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What is the oxidation number of Cr in
K2Cr2O7?
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4.
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Which of the following is the INCORRECT
statement?
a. | Reduction results in a decrease in oxidation
number. | b. | The oxidation number of oxygen atoms in ozone,
O3, is zero. | c. | Reduction is a
loss of electrons. | d. | The oxidizing
agent in a redox reaction is reduced. | e. | Electrons are
being transferred in a redox reaction. |
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5.
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Which substance is being oxidized in the following
reaction?
Zn(s) + 4 CN-(aq) +
Ag2CrO4(s) ® [Zn(CN)
4]2- + 2 Ag(s) + CrO42-(aq)
a. | CN- (aq) ions | b. | Ag(s) | c. | Zn(s) | d. | Ag+(aq)
ions | e. | H2 (g) |
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6.
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What is the oxidation number of Cl in
HClO2?
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7.
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Identify the INCORRECT statement in the
following:
a. | One Faraday of charge will reduce exactly one mole of
Zn2+ ions to Zn(s). | b. | In an electrolytic
cell a nonspontaneous reaction is made to take place by applying an external electric
current. | c. | The cathode is the site of reduction in an
electrochemical cell. | d. | Measuring the
potential of a cell provides a direct determination of the free energy of the cell
reaction. | e. | Sodium metal and chlorine gas are produced in an
electrolytic cell containing pure molten NaCl. |
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8.
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How many grams of Ag(s) could be plated out on the
cathode of an electrolytic cell by the passage of 5.0 Amps of current through AgNO3
solution for 1 hour? Faraday's number = 96485 Coul/mol.
a. | 5.5 x 10-3 g | c. | 5.2 x 10-5 g | b. | 0.19
g | d. | 20 g |
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9.
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Copper can exist in solution as Cu+ or
Cu2+. Suppose a 1.00 Amp current applied for 30.0 minutes produced 1.185 grams of Cu(s).
What oxidation state is the copper in solution?
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10.
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Referring to the table of Standard Cell Potentials
below, determine the standard cell potential for the following reaction:
Pb2+(aq) + 2 Cl-(aq) ®
Pb(s) + Cl2
Standard reduction potential E°
Pb2+(aq) +
2e- ® Pb(s) -0.126
Cl2 + 2e- ® 2
Cl-(aq) +1.360
a. | +1.486 | c. | +1.234 | b. | -1.486 | d. | -1.234 |
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11.
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Which metal is most easily oxidized to its cationic
form?
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12.
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In the Daniell cell the overall reaction is:
Zn(s) + Cu2+(aq) ®
Zn2+(aq) + Cu(s)
Which of the following reactions is taking place at the
cathode?
a. | Cu2+(aq) + 2e- ® Cu(s) | c. | Cu(s)
® Cu2+(aq) + 2e- | b. | Zn(s) ® Zn2+(aq) +
2e- | d. | Zn2+(aq) + 2e- ®
Zn(s) |
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