VOLTAIC CELL QUIZ Part II

1.The equation that represents a reaction that is not a redox reaction is ….
1. Zn + CuSO4 → ZnSO4 + Cu
2. 2H2O2 → 2H2O + O2
3. H2O + CO2 → H2CO3
4. 2H2 + O2 → 2H2O
a.Reaction 1
b.Reaction 2
c.Reaction 3
d.Reaction 4
e.All of these are redox reactions
2.For the galvanic cell described below, the correct line notation is ….
Cl2 + 2e- → 2Cl- (E0 = 1.36v)
Cu+ + e- → Cu (E0 = 0.52v)
a.Pt(s)|Cl2(g)|2Cl-(aq)||Cu(s)|Cu+(aq)
b.Pt(s)|Cu(s)|Cu+(aq)||Cl2(g)|2Cl-(aq)|Pt(s)
c.Cu(s)|Cu+(aq)||Cl2(g)|2Cl-(aq)
d.Pt(s)|Cl2(g)|2Cl-(aq)||Cu(s)|Cu+(aq)|Pt(s)
e.Cu(s)|Cu+(aq)||Cl2(g)|2Cl-(aq)|Pt(s)
3.What is indicated when a chemical cell's voltage (E) has dropped to zero?
a) The concentration of the reactants has increased.
b) The concentration of the products has decreased.
c) The cell reaction has reached equilibrium.
d) The cell reaction has completely stopped.
4.Given the redox reaction:
2 Cr(s) + 3 Cu2+(aq) --> 2 Cr3+(aq) + 3 Cu(s)
Which reaction occurs at the cathode in an electrochemical cell?
a) reduction of Cu2+(aq)
b) reduction of Cu(s)
c) oxidation of Cr3+(aq)
d) oxidation of Cr(s)
5.Given the cell reaction:
2 H2O(l)  2 H2(g) + O2(g)
The cell is best described as
a) an electrolytic cell in which an exothermic reaction occurs
b) an electrolytic cell in which an endothermic reaction occurs
c) a galvanic cell in which an exothermic reaction occurs
d) a galvanic cell in which an endothermic reaction occurs
6.In an electrochemical cell, what is the purpose of the salt bridge?
a) It is the anode.
b) It is the cathode.
c) It permits the migration of ions between the half-cells.
d) It permits the mixing of solutions between the half-cells.
7.In a voltaic cell what type of ions move toward the cathode?
a. anions
b. cations
c. neither cations nor anions
d. freons
e. both cations and anions
8.What is the equation for the net cell reaction for the electrochemical cell:
Pb(s) | PbI2(s) | HI(aq) | H2(g) | Pt(s)
a. Pb(s) + 2I-(aq) --> PbI2(s) + 2e-
b. 2H+(aq) + 2e- --> H2(g)
c. Pb(s) + 2HI(aq) --> PbI2(s) + H2
d. both a and b
e. none of the above
9.Referring to the table of Standard Cell Potentials below, determine the standard cell potential for the following reaction running in this direction:
2 Fe3+(aq) + Zn(s) --> 2 Fe2+(s) + Zn2+(aq)
a) -2.30 V
b) +0.01 V
c) +0.78 V
d) +1.53 V
e) +2.30 V
STANDARD REDUCTION POTENTIALS E°(volts)
F2 + 2 e- ---> 2 F- E0 = +2.87
Au+ + e- ---> Au Eo = +1.69
Ag+ + e- ---> Ag Eo = +0.80
Fe3+ + e- ---> Fe2+ Eo = +0.77
Cu2+ + 2 e- ---> Cu Eo = +0.34
2 H+ + 2 e- ---> H2 Eo = 0
Pb2+ + 2 e- ---> Pb Eo = -0.13
Fe2+ + 2 e- ---> Fe Eo = -0.44
Zn2+ + 2 e- ---> Zn Eo = -0.76
Na+ + e- ---> Na Eo = -2.71
Li+ + e- ---> Li Eo = -3.05
10.Which of the following metal ions in aqueous solution is most easily oxidized to its aqueous ionic form?
a) Na
b) Pb
c) Zn
d) Ag
11.Which metal is used as a coating on steel to limit corrosion?
a) Na
b) Ca
c) K
d) Zn
12.Given the nickel-cadmium battery reaction:
2 NiOOH + Cd + 2 H2O --> 2 Ni(OH)2 + Cd(OH)2
What occurs during discharge in the nickel-cadmium battery?
a) Ni3+ is reduced to Ni2+.
b) Ni2+ is reduced to Ni3+.
c) Ni3+ is oxidized to Ni2+.
d) Ni2+ is oxidized to Ni3+.
13.Referring to the table of standard cell potentials attached, determine the standard cell potential of the following reaction for the corrosion of iron in an acidic environment:
Fe(s) + 2 H+(aq) +1/2 O2(g) --> Fe2+(aq) + H2O(l)
a) +0.44 V
b) +0.79 V
c) -0.79 V
d) +1.23 V
e) +1.67 V
14.Which ion in solution is most easily reduced to its elemental form?
a) Na+
b) Cu2+
c) Mg2+
d) Zn2+
15.In the alkaline energy cell the overall reaction is: Zn(s) + 2MnO2 (s) +2 H2O ---> Zn(OH)2(s) + 2MnO(OH) (s). Which of the following half-reactions is taking place at the cathode?
a) Zn2+(aq) + 2e- ---> Zn(s)
b) Zn(s) ---> Zn2+(aq) + 2e-
c) Zn(s) + 2OH-(aq)  Zn(OH)2(s) + 2e-
d) 2 MnO2(s) +2 H2O + 2e- ---> 2MnO(OH)(s) + 2OH- (aq)
16.In the lead storage battery the product of both the cathode and anode reactions is?
a) PbSO4
b) PbO2
c) Pb
d) H2SO4
17.The fuel cell we discussed in class forms the following product:
a) H2
b) H2SO4
c) H2O
d) H2S
e) O2
18.In an alkaline energy cell the overall cell reaction is as follows:
Zn(s) + 2 MnO2(s) + 2 H2O --> Zn(OH)2(s) + 2 MnO(OH)
Which of the following reactions is taking place at the cathode?
a) 2 MnO2(s) + 2 H2O + 2e- --> Zn(OH)2(s) + 2 MnO(OH)(s)
b) 2 MnO2(s) + 2 H2O + 2e- --> 2 MnO(OH)(s) + 2 OH-
c) Zn(s) + 2 OH-(aq) --> Zn(OH)2(s) + 2e-
d) Zn(OH)2(s) + 2e-  Zn(s) + 2 OH-(aq)
19.In a Nickel-Cadmium cell the following overall reaction is taking place:
Cd(s) + NiO2(s) + 2 H2O Cd(OH)2(s) + Ni(OH)3(s)
Which of the following half-reactions are taking place at the anode?
a) NiO2(s) + 2 H2O + 2e- --> Ni(OH)2(s) + 2 OH-
b) Cd(s) + 2 OH-(aq) --> Cd(OH)2(s) + 2e-
c) Cd(OH)2(s) + 2e- --> Cd(s) + 2 OH-(aq)
d) Ni(OH)2(s) + 2 OH- --> NiO2(s) + 2 H2O + 2e-