Multiple Choice Questions for Electrochemical Cell
____ 1. Oxidation is
a. a
gain of electrons. c. a decrease in oxidation number
b. an
increase in oxidation number. d. removal of oxygen.
2. The
oxidation number of sodium in a compound is
a. 0 c. +1
b. +2 d. -1
3.
Which of the following is an oxidation?
a. Fe+3 + e-
à Fe+2 c.
Fe à Fe+2 + 2e-
b. Fe+3 + 3e- à Fe d. Cl
+ e- à Cl-
4.
Which of the following would be the best reducing agent?
a.
Cl2 c. O-2
b. F- d. Na+
5.
What is the oxidation state of S in H2SO3?
a. +2 c. 0
b. +4 d. +6
6.
What is the oxidation number of Br in the BrO3- ion?
a. -1 c. +5
b. +1 d. +7
7.
What kind of reaction is Cl2 à Cl- + ClO2-(
aside from unbalanced)?
a. An
oxidation c. an imposible reaction
b. A
reduction d. a disproportionation
8. In the reaction HNO2 + I-
à NO + I2, what atoms are being oxidized and reduced
respectively?
a. O,
I c. I, N
b. I,
O d. N, I
9.
What is the next step in
balancing the half reaction Cr2O7-2 à
2 Cr+3?
a. add
7 H2O to the right c. add 3.5 O2 to the left
b. add
7 H2O to the left d. add 8 electrons to the left
10.
What is the next step in balancing the reaction SO3-2 + H2O à SO4-2 + 2H+?
a. add
3 H2O to the left c. add 2 electrons to the left
b. add
2 electrons to the right d. multiply through by 2
11.
What is wrong with the REDOX reaction
2 Cl- + 2Br- à Cl2 + Br2?
a. nothing
is being oxidized c. chloride cannot be oxidized
b. nothing
is being reduced d bromide cannot be oxidized
12. The
process by which electricity is used to bring about a chemical change is called
a. corrosion. c. electrolysis.
b. voltage. d. oxidation.
13. An electrochemical cell in which electrical
energy drives nonspontaneous redox reactions.
a. electrochemical
cell c. voltaic cell
b. electrolytic
cell d. rechargeable battery
14. In a chemical cell composed of two half
cells, ions are allowed to flow from one half-cell to the other by means of
a. electrodes. c. a voltmeter.
b. a
wire. d. a salt bridge.
15. The following reaction takes place in the
electrolytic cell:
Zn(s) + Cu+2(aq) à Zn+2(aq) +
Cu(s)
Which of the following
statements is incorrect?
a. Zinc
is oxidized while copper ion is reduced.
b. Zinc
is the reductant while copper ion is the oxidant.
c. Zinc
loses two electrons while copper ion gains two electrons.
d. Zinc
undergoes reduction while copper ion undergoes oxidation.
16. Which
of the following is not produced by the electrolysis of aqueous NaCl?
a. Na c. NaOH
b. Cl2 d. H2
17. In
voltaic cell reduction occurs at the
a. anode. c. salt bridge.
b. electrolyte.
d. cathode.
18. In
the reaction for a nickel-cadmium battery,
2Ni(OH)3 +
Cd à 2Ni(OH)2 +
Cd(OH)2
Which species is oxidized
during the discharge of the battery.
a. Ni+3 c. Cd
b. Ni+2 d. Cd+2
19. Which statement is incorrect
about an electrolytic cell?
a.
The cell includes a battery.
b.
Reduction occurs at the cathode.
c.
The cell reaction is spontaneous.
d.
The electrodes may be inert (e.g.
graphite) or may be involved in the cell reaction
20. Which statement is true for an electrochemical
cell?
a.
Oxidation occurs at the anode only.
b. Reduction occurs at the
anode only.
c. Oxidation occurs at both
the anode and cathode.
d. Reduction occurs at both the anode and
cathode.
21. An iron ring is plated with zinc metal in the
apparatus below.
Which of the following is
true?
a. It is a voltaic cell and the reaction is spontaneous.
b. It is a voltaic cell and the reaction is not spontaneous.
c. It is an electrolytic cell and the reaction is spontaneous.
d. It is an electrolytic cell and the reaction is
not spontaneous.
22. Which
one of the following reactions is a redox reaction?
a. Pb2+(aq) + 2Cl-(aq)
à PbCl2(s)
b. NaOH(aq) + HCl(aq) à NaCl(aq) + H2O(l)
c. AgNO3(aq) + HCl(aq) à AgCl(s) + HNO3(aq)
d. 2Al(s) + 3Cl2(g) à 2AlCl3(s)
23. What is the term for the
electrode where oxidation occurs?
a.
anode c.
cathode
b. oxidizing agent d. reducing agent
24. Which of the
following is true for an electrolytic cell?
a. An electric current is produced by a chemical
reaction.
b.
A nonspontaneous reaction is forced to
occur.
c. Electrons flow towards the anode.
d. Electrons flow through the salt bridge.
25. The cell potential, E°, for
an oxidation-reduction reaction was found to equal 1.10 V. What can be said about this reaction?
a. at equilibrium c. endothermic
b. nonspontaneous d.
spontaneous
26. In an
electrochemical cell, electrons travel in which direction?
a.
from the anode to the cathode through the external circuit
b. from the anode to the
cathode through the porous cup
c. from the cathode to the
anode through the external circuit
d. from the cathode to the
anode through the porous cup.
27. The diagram shows the electrolysis of molten
KCl. What occurs when the switch is closed?
a. Positive ions move toward the anode and gain
electrons.
b. Positive ions move toward the anode and lose
electrons.
c. Positive ions move toward the cathode and
gain electrons.
d. Positive ions move toward the cathode and lose
electrons.
28. An
electrochemical cell is set up with a copper electrode in contact with 1.0
mol/L CuSO4(aq) and a lead
electrode in contact with 1.0 mol/L Pb(NO3)2(aq)
. The standard reduction potentials are
At 25° C, the standard cell potential for this galvanic
cell in volts is a.
a.
0.13 c. 0.21
b.
0.34 d. 0.94
29. Consider
the following:
In an electrochemical cell, the combination of
electrodes (and corresponding electrolytes) that would produce highest voltage
is
a.
c. 
c.
b.
d. 
d.
30. An electric
cell consists of a silver electrode in 1.0 mol/L solution of 
(silver nitrate), a copper electrode
in 1.0 mol/L solution of 
(copper nitrate) and a salt bridge. The
spontaneous cell reaction is
(silver nitrate), a copper electrode
in 1.0 mol/L solution of (copper nitrate) and a salt bridge. The
spontaneous cell reaction is
When two electrodes are
connected by a wire, which of the following does not take place?
a. Electrons
flow in the wire from the copper electrode to the silver electrode.
b. The
silver electrode increases in mass as the cell operates.
c. There
is a net movement of silver ions through the salt bridge from the silver
half-cell to the copper half-cell.
d. There
is a net movement of copper ions through the salt bridge from the copper
half-cell to the silver half cell
No comments:
Post a Comment