General Chemistry, 11e (Petrucci)
Chapter 19 Electrochemistry
1) In a galvanic cell, oxidation occurs at the cathode.
2) E°cell is the standard cell potential.
3) When Ecell < 0, the reaction is spontaneous.
4) The Ecell for the following concentration cell at 25 °C is 0.006 V.
Pt ∣ H2 (g, 0.025 atm) ∣ H+ (0.012 M) H+ (1 M) ∣ H2 (g, 1 atm) ∣ Pt
2 H+(aq) + 2 e– → H2(g) E° = 0. V
5) The hydrogen standard electrode is the most convenient standard electrode to use.
6) Primary batteries’ cell reactions cannot be reversed.
7) A primary battery is recharged by passing electricity through the battery.
8) The active metal is called a sacrificial cathode.
9) Cathodic protection is attaching a more active metal to the protected metal.
10) Corrosion of metals is an oxidation-reduction process.
11) In the electrolysis of water, oxygen is evolved at the cathode.
12) Choose the INCORRECT statement.
A) Electrons are transferred in oxidation-reduction reactions.
B) A strip of metal in a solution of ions of that metal is an electrode potential.
C) Reduction is the gain of electrons.
D) Oxidation is the loss if electrons.
E) A salt bridge maintains electrical contact between two half cells.
13) Choose the INCORRECT statement.
A) An electrode is often a strip of metal.
B) An electrode in a solution of its ions is a half cell.
C) An electrochemical cell is a half cell.
D) The electromotive force (emf) is the cell potential.
E) The cell potential is the potential difference between the half cells.
14) Choose the INCORRECT statement.
A) A cell diagram is a symbolic way to show cell components.
B) An anode is where oxidation occurs.
C) A cathode is where reduction occurs.
D) Half cells in a cell diagram are separated by a single vertical line.
E) The anode is on the left in a cell diagram.
15) In a galvanic cell, oxidation occurs at the:
A) anode
B) cathode
C) salt bridge
D) electrolyte
E) in cathodic space
16) Choose the INCORRECT statement.
A) A double vertical line separates half cells in a cell diagram.
B) A single vertical line separates phases in a cell diagram.
C) A voltaic cell is a galvanic cell.
D) Voltaic cells produce an electron flow.
E) Electrolytic cells are cells where electron flow is caused by spontaneous reactions.
17) In a zinc-lead cell the reaction is:
Pb2+(aq) + Zn(s) → Pb(s) + Zn2+(aq) E° = 0.637 V
Which of the following statements about this cell is FALSE?
A) The zinc electrode is the cathode.
B) The reaction will go in the direction indicated.
C) The shorthand notation is Zn(s) ∣ Zn2+(aq) Pb2+(aq) ∣ Pb(s).
D) The actual cell voltage is less than +0.637 volts because of concentration polarization and possible
other factors.
E) The lead electrode is positively charged.
18) Choose the correct statement based on the following oxidation potentials.
Mg/Mg2+ +2.37 v Fe/Fe2+ +0.44 v Cu/Cu2+ -0.34 v
Zn/Zn2+ +0.76 v Sn/Sn2+ +0.14 v Ag/Ag+ -0.80 v
A) Mg will not displace Zn2+ from solution
B) Cu will displace Sn2+ from solution
C) Fe will displace Zn2+ from solution
D) Fe will displace H+ from solution
E) Sn will displace Fe2+ from solution
19) Choose the INCORRECT statement.
A) SHE stands for Standard Helium Electrodes.
B) E° is the standard electrode potential.
C) The standard electrode potential is the reduction potential of a half cell.
D) The standard cell potential is the potential difference between two half cells.
E) E°cell is the standard cell potential.
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20) Choose the INCORRECT statement.
A) When a half reaction is reversed, the sign of the potential is changed.
B) Reversing a half reaction makes it a reduction potential.
C) Each electrochemical cell consists of a reduction half cell and an oxidation half cell.
D) A voltaic cell is also called a battery.
E) The potential difference of a cell is the voltage of the cell.
21) Determine E°cell for the reaction: 2 Al(aq) + 3 Zn2+(aq) → 2 Al3+(aq) + 3 Zn(s). The half reactions are:
Al3+(aq) + 3 e– → Al(s) E° = -1.676 V
Zn2+(aq) + 2 e– → Zn(s) E° = -0.763 V
A) 0.913 V
B) -2.439 V
C) 2.439 V
D) -1.063 V
E) -0.913 V
22) Determine E°cell for the reaction: 2 Ag+(aq) + Mg(s) → 2 Ag(s) + Mg2+(aq). The half reactions are:
Mg2+(aq) + 2 e– → Mg(s) E° = -2.356 V
Ag+(aq) + e– → Ag(s) E° = 0.800 V
A) 0.756 V
B) -0.756 V
C) 3.156 V
D) -1.556 V
E) 1.556 V
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23) Determine E°cell for the reaction: Pb2+(aq) + Zn(s) → Pb(s) + Zn2+(aq). The half reactions are:
Pb2+(aq) + 2 e– → Pb(s) E° = -0.125 V
Zn2+(aq) + 2 e– → Zn(s) E° = -0.763 V
A) 0.638 V
B) -0.638 V
C) 0.888 V
D) -1.276 V
E) -0.888 V
24) Choose the INCORRECT statement.
A) The work available in a cell = –zFEcell.
B) ΔG ° = –zFE°cell
C) When Ecell < 0, the reaction is spontaneous.
D) When Ecell = 0, the reaction is at equilibrium.
E) Reversing a cell reaction changes the sign of Ecell.
25) For the reaction: Mg(s) + AgNO3(aq) → Ag(s) + Mg(NO3)2(aq)
Ag+(aq) + e– → Ag(s) E° = 0.800 V
Mg2+(aq) + 2 e– → Mg(s) E° = -2.356 V
Is the reaction spontaneous and why?
A) No, Mg(s) does not react with Ag+.
B) No, E° is a positive value.
C) No, E° is a negative value.
D) Yes, E° is a positive value.
E) Yes, E° is a negative value.
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26) What is the cell diagram for the spontaneous cell involving the Fe3+(aq) ∣ Fe2+(aq) ∣ Pt(s) (0.771V) half
cell and the Zn2+(aq) ∣ Zn(s) (-0.763 V) half cell?
A) Fe2+(aq) ∣ Fe3+(aq) Zn2+(aq) ∣ Zn(s)
B) Pt(s) ∣ Fe2+(aq), Fe3+(aq) Zn2+(aq) ∣ Zn(s)
C) Zn(s) ∣ Zn2+(aq) Fe3+(aq) ∣ Fe2+(aq) ∣ Pt(s)
D) Zn(s) ∣ Zn2+(aq) Fe3+(aq) ∣ Fe2+(aq)
E) Zn(s) ∣ Zn2+(aq) Fe3+(aq) ∣ Fe2+(aq) ∣ Zn(s)
27) If the voltage of an electrochemical cell is negative then the cell reaction is:
A) nonspontaneous
B) slow
C) exothermic
D) spontaneous
E) fast
28) For the reaction: Mg(s) + AgNO3(aq) → Ag(s) + Mg(NO3)2(aq)
Ag+(aq) + e– → Ag(s) E° = 0.800 V
Mg2+(aq) + 2 e– → Mg(s) E° = -2.356 V
Estimate Keq at 25 °C.
A) 5.7 × 10106
B) 2.0 × 1053
C) 3.7 × 1052
D) 1.1 × 1027
E) 10-107
29) Calculate the Ksp of lead iodide from the following standard electrode potentials, at 25 °C:
2 e– + PbI2(S) → Pb(s) + 2 I–(aq) E° = -0.365 V
2 e– + Pb2+(aq) → Pb(s) E° = -0.126 V
A) 8 × 10–9
B) 9 × 10–5
C) 2 × 10-17
D) 5 × 10-13
E) 6 × 10–5
30) In the cell Pt(s) ∣ Fe2+(aq) ∣ Fe3+(aq) Cu2+(aq) ∣ Cu(s) which will increase the cell voltage the most?
A) Halve [Cu2+].
B) Halve [Fe2+].
C) Double [Cu2+].
D) Double [Fe2+].
E) Cut Cu electrode in half.
31) Which of the following are commonly used as alternate standard electrodes:
I) Ag(s) | AgCl(s) | Cl– ((aq, 1.0 M)
II) Hg(l) | HgCl2(s) | Cl– (aq, 1.0 M)
III) Ag(s) | AgCl(s) | Cl– ((aq, 1.0 M)
IV) Hg(l) | Hg2Cl2(s) | Cl– (aq, 1.0 M)
V) Hg(s) | Hg2Cl2(s) | Cl– (aq, 1.0 M)
A) I) and V)
B) II) and IV)
C) I) and IV)
D) II) and III)
E) I) and III)
32) Glass electrodes are used for direct measurement of:
A) pH
B) pKa
C) Ksp
D) Q
E) pKw
33) Determine the Ksp at 25 °C of AgCl(s). The half-reactions are:
Ag+(aq) + 1 e– → Ag(s) E° = +0.771 V
AgCl(s) + 1 e– → Ag(s) + Cl–(aq) E° = +0.222 V
A) 1 × 10–2
B) 0.771
C) 4 × 1011
D) 5 × 10–10
E) 4 × 10-11
34) Consider the cell:
Ni(s) ∣ Ni2+ (aq, ?M) Cu2+ (aq, 0.136 M) ∣ Cu(s)
Ni2+(aq)/Ni(s) E° = -0.257 V Cu2+(aq)/Cu(s) E° = 0.340 V
The measured potential of the cell is 0.621 V. What is [Ni2+] at 25 °C?
A) 2 × 10-2 M
B) 1 M
C) 4 × 10–42 M
D) 0.05 M
E) 0.4 M
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35) What is the concentration of Cu2+(aq) in the following cell at 25 °C if the cell voltage is 1.253 V?
Zn(s) ∣ Zn2+ (aq, 0.125 M) Cu2+(?) ∣ Cu(s)
Cu2+(aq) + 2 e– → Cu(s) E° = 0.340 V
Zn2+(aq) + 2 e– → Zn(s) E° = –0.763 V
A) 0.6 M
B) 1 × 10-2 M
C) 1 × 10-6 M
D) 9 × 10-4 M
E) 4 × 10-4 M
36) What is the concentration of Al3+(aq) in the following cell at 25 °C if the cell voltage is 1.486 V?
Al(s) ∣ Al3+(aq, ?) Sn2+(aq, 3.21 × 10-4 M) ∣ Sn(s)
Al3+(aq) + 3 e– → Al(s) E° = -1.676 V
Sn2+(aq) + 2 e– → Sn(s) E° = -0.137 V
A) 2.8 × 10-3 M
B) 1.6 × 10-5 M
C) 4.5 × 10-5 M
D) 2.4 × 10-2 M
E) 7.8 × 10-6 M
37) Choose the INCORRECT statement.
A) A concentration cell consists of half cells with identical electrodes but different ion concentrations.
B) Primary batteries’ cell reactions cannot be reversed.
C) Secondary batteries’ cell reaction can be reversed.
D) A primary battery is recharged by passing electricity through the battery.
E) Cells can be joined in series to increase the total voltage.
38) The lithium-ion battery is based on:
A) Li+(aq)/Li(s) couple
B) Co3+(aq)/Co2+(aq) couple
C) Co(III)/Co(IV) couple
D) both Li+(aq)/Li(s) and Co3+(aq)/Co2+(aq)
E) both Li+(aq)/Li(s) and Co(III)/Co(IV)
39) Choose the INCORRECT statement.
A) Corrosion of metals is an oxidation reduction process.
B) Rust is a form of corrosion.
C) Metals can be protected by cathodic protection.
D) Cathodic protection is attaching a more active metal to the protected metal.
E) The active metal is called a sacrificial cathode.
40) Choose the INCORRECT statement.
A) One mole of hydrogen ions will have a positive charge of one Faraday.
B) One Faraday of charge will release 35.5 g of Cl2(g) in the electrolysis of a chloride solution.
C) One Faraday of charge will plate out two moles of Cu(s) from a solution of CuSO4(aq).
D) One mole of electrons has a charge of l Faraday.
E) One mole of hydrogen gas requires 2 Faradays.
41) One mole of electrons has a charge of:
A) 96,485 A
B) 1.60 × 10-19
C) 6.02 × 1023 A
D) 96,485 C
E) 96,485 F
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42) An electrolysis is carried out by passing an electric current through a solution of copper sulfate using
inert electrodes. This causes:
A) Cu(s) to plate out on the negative electrode
B) Cu(s) to plate out on the anode
C) oxygen to form on the negative electrode
D) H2(g) to form at the negative electrode
E) sulfur to form on the positive electrode
43) Choose the INCORRECT completion of the following sentence:
“In the electrolysis of water…
A) …a direct current must be used.”
B) …oxygen is evolved at the cathode.”
C) …electrical energy must be supplied continuously because it is an endothermic reaction.”
D) …the volume of hydrogen produced is twice the volume of oxygen produced.”
E) ….one mole of H2(g) is produced for each two moles of electrons.”
44) How many coulombs would be needed to deposit all of the Ag+(aq) ion from 600 mL of a solution
0.250 M in Ag+(aq)?
A) 1.45 × 107 C
B) 1.56 × 106 C
C) 1.45 × 104 C
D) 2.41 × 104 C
E) 1.56 × 104 C
45) The following half-reactions are used in the zinc-air battery.
(aq) + 2 e– → Zn(s) + 4 OH–(aq) E° = -1.199 V
O2(g) + 2 H2O(l) + 4 e– → 4 OH–(aq) E° = +0.401 V
How much charge is transferred per gram Zn(s) in this voltaic cell?
A) 5.90 × 103 C
B) 2.95 × 103 C
C) 1.47 × 103 C
D) 3.39 × 10-4 C
E) 1.69 × 10-4 C
46) Write the net redox reaction that occurs in the galvanic cell.
Zn(s) ∣ Zn+2(aq) Pb+2(aq) ∣ Pb(s)
A) Pb(s) + Zn(s) → Pb+2(aq) + Zn+2(aq) + 4 e–
B) Pb(s) + Zn+2(aq) → Pb+2(aq) + Zn(s)
C) Pb+2(s) + Zn+2(s) → Pb(s) + Zn(s) + 4 e–
D) Pb+2(aq) + Zn(s) → Zn+2(aq) + Pb(s)
E) Pb(s) + Zn(s) + 4 e– → Pb+2(aq) + Zn+2(aq)
47) For the reaction: Mg(s) + 2 AgNO3(aq) → 2 Ag(s) + Mg(NO3)2(aq)
Write a voltaic diagram for the reaction.
A) Ag(s) | Ag(aq) Mg2+(aq) | Mg(s)
B) Mg(s) ∣ Mg2+ Ag+ (aq) ∣ Ag (s)
C) Mg(s) ∣ Mg2+ Ag(s) ∣ Ag+ (aq)
D) Ag(aq) ∣ Ag(s) Mg(s) ∣ Mg2+ (aq)
E) Ag(s) ∣ Mg2+ (aq) Ag+ (aq) ∣ Mg(s)
48) Write the net redox reaction that occurs in the following galvanic cell.
Ti(s) ∣ Ti3+(aq) Se(s) | Se2-(aq)
A) Ti(s) + Se2-(aq) + 1 e– → Ti3+(aq) + Se(s)
B) 2 Ti(s) + 3 Se(s) → 2 Ti3+(aq) + 3 Se2-(aq)
C) Ti(s) + Se(s) → Ti3+(aq) + Se2-(aq) + 1 e–
D) 2 Ti3+(aq) + 3 Se(s) → 2 Ti(s) + 3 Se2-(aq)
E) 2 Ti3+(aq) + 3 Se(s) + 1 e– → 2 Ti(s) + 3 Se2-(aq)
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49) For the reaction: Mg(s) + AgNO3(aq) → Ag(s) + Mg(NO3)2(aq)
Ag+(aq) + e– → Ag(s) E° = 0.800 V
Mg2+(aq) + 2 e– → Mg(s) E° = -2.356 V
For the reaction, determine E° for the cell.
A) 1.556 V
B) -3.156 V
C) 3.156 V
D) 0.800 V
E) 2.356 V
50) Given the table below predict the numerical value of the standard cell potential for the reaction:
2 Cr(s) + 3 Cu2+(aq) → 2 Cr3+(aq) + 3 Cu(s)
Half Reaction E° (volts)
(1) Cr3+(aq) + 3 e– → Cr(s) -0.74
(2) Cr3+(aq) + e– → Cr2+(aq) -0.41
(3) Cr2O72-(aq) + 14 H+(aq) + 6 e– → 2 Cr3+(aq) + 7 H2O(l) 1.33
(4) Cu+(aq) + e– → Cu(s) 0.52
(5) Cu2+(aq) + 2 e– → Cu(s) 0.34
(6) Cu2+(aq) + e– → Cu+(aq) 0.16
A) 2.50 volts
B) 0.417 volts
C) -1.08 volts
D) 1.08 volts
E) -0.40 volts
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51) Determine E°cell for the reaction: Pb(s) + Zn2+(aq) → Pb2+(aq) + Zn(s). The half reactions are:
Pb2+(aq) + 2 e– → Pb(s) E° = -0.125 V
Zn2+(aq) + 2 e– → Zn(s) E° = -0.763 V
A) 0.638 V
B) -0.638 V
C) 0.888 V
D) -1.276 V
E) -0.888 V
52) Determine E°cell for the reaction: Pb(s) + Cu2+(aq) → Pb2+(aq) + Cu(s). The half reactions are:
Pb2+(aq) + 2 e– → Pb(s) E° = -0.125 V
Cu2+(aq) + 2 e– → Cu(s) E° = 0.340 V
A) 0.215 V
B) 0.465 V
C) 0.930 V
D) -0.215 V
E) -0.465 V
53) Determine E°cell for the reaction: 2 Al3+(aq) + 3 Zn(s) → 2 Al + 3 Zn2+(aq). The half reactions are:
Al3+(aq) + 3 e– → Al(s) E° = -1.676 V
Zn2+(aq) + 2 e– → Zn(s) E° = -0.763 V
A) 0.913 V
B) -2.439 V
C) 2.439 V
D) -1.063 V
E) -0.913 V
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54) Determine E°cell for the reaction: 2 Ag(s) + Mg2+(aq) → 2 Ag+(aq) + Mg.(s) The half reactions are:
Mg2+(aq) + 2 e– → Mg(s) E° = -2.356 V
Ag+(aq) + e– → Ag(s) E° = 0.800 V
A) 0.756 V
B) -0.756 V
C) 3.156 V
D) -3.156 V
E) 1.556 V
55) Determine E°cell for the reaction: I2(s) + Cu(s) → 2 I–(aq) + Cu2+(aq). The half reactions are:
I2(s) + 2 e– → 2 I–(aq) E° = +0.535 V
Cu2+(aq) + 2 e– → Cu(s) E° = 0.340 V
A) 0.730 V
B) –0.875 V
C) 0.875 V
D) 0.195 V
E) -0.195 V
56) Determine E°cell for the reaction: Cl2(g) + 2 F–(aq) → 2 Cl–(aq) + F2(g). The half reactions are:
F2(g) + 2 e– → 2 F–(aq) E° = +2.866 V
Cl2(g) + 2 e– → 2 Cl–(aq) E° = 1.358 V
A) 3.016 V
B) -4.224 V
C) 1.508 V
D) 4.224 V
E) -1.508 V
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57) Determine E°cell for the reaction: MnO4–(aq) + 8 H+(aq) + 5 Fe2+(aq) → Mn2+(aq) + 4 H2O(l) + 5
Fe3+(aq). The half reactions are:
Fe3+(aq) + e– → Fe2+(aq) E° = +0.771 V
MnO4–(aq) + 8 H+(aq) + 5 e– → Mn2+(aq) + 4 H2O(l) E° = 1.507 V
A) -2.34 V
B) -2.28 V
C) 2.28 V
D) -0.74 V
E) 0.74 V
58) Will magnesium metal displace Al3+(aq) ion from an aqueous solution?
Mg2+(aq) + 2 e– → Mg(s) E° = -2.356 V
Al3+(aq) + 3 e– → Al(s) E° = -1.676 V
A) No, since E°cell is negative.
B) Yes, since E°cell is negative.
C) No, the reverse reaction is spontaneous.
D) Yes, since E°cell is positive.
E) No, the system is at equilibrium.
59) Determine E°cell at 25 °C for the following reaction:
Pb2+(aq) + Cu(s) → Cu2+(aq) + Pb(s)
The half-reactions are:
Pb2+(aq) + 2 e– → Pb(s) E° = -0.125 V
Cu2+(aq) + 2 e– → Cu(s) E° = +0.337 V
A) 0.212 V
B) -0.462 V
C) 0.462 V
D) -0.212 V
E) 0.424 V
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60) Determine E°cell at 25 °C for the following reaction:
3 Sn2+(aq) + 2 Al(s) → 2 Al3+(aq) + 3 Sn(s)
Al3+(aq) + 3 e– → Al(s) E° = -1.676 V
Sn2+(aq) + 2 e– → Sn(s) E° = -0.137 V
A) 2.941 V
B) -1.813 V
C) 1.813 V
D) -1.539 V
E) 1.539 V
61) For the cell reaction at 25 °C Cu2+(aq) + Zn(s) → Cu(s) + Zn2+(aq), E°cell = +1.100 V. What is the
equilibrium constant for this reaction?
A) 3 × 10-19
B) 2 × 1037
C) 2 × 10-37
D) 3 × 1018
E) 3 × 10-18
62) The following galvanic cell has a measured cell potential E°cell = 0.646 V.
Pt(s) ∣ Sn4+(aq), Sn2+(aq) Ag+(aq) ∣ Ag(s)
Given that the standard reduction potential for the reduction of Ag+(aq) to Ag(s) is +0.800 V, what is the
standard reduction potential for the Sn4+/Sn2+ half-reaction?
A) +0.154 V
B) -0.154 V
C) +1.45 V
D) -1.45 V
E) +0.308 V
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63) What is the cell diagram for the spontaneous cell involving the Cl2(g) ∣ Cl-(aq) (1.358 V) and the
Sn2+(aq) ∣ Sn(s) (-0.137V) half cells?
A) Pt(s) ∣ Cl2(g) ∣ Cl–(aq) Sn2+(aq) ∣ Sn(s)
B) Sn(s) ∣ Sn2+(aq) Cl–(aq) ∣ Cl2(g) ∣ Pt(s)
C) Cl2(g) ∣ Cl–(aq) Sn2+(aq) ∣ Sn(s)
D) Sn(s) Sn2+(aq) Cl–(aq) ∣ Cl2(g)
E) Sn(s) ∣ Cl–(aq) Sn2+(aq) ∣ Sn(s)
64) What is the cell reaction of the spontaneous cell made from the Zn2+(aq)/Zn(s) (-0.76 V) and Br2(l)/2
Br–(aq)(1.07 V) half cells?
A) 2Br–(aq) + Zn2+(aq) → Zn + Br2(l)
B) Br2(l) + Zn → Zn2+(aq) + 2Br–(aq)
C) 2Br–(aq) + Zn → Br2(l) + Zn2+(aq)
D) Br2(l) + Zn → Zn2+(aq) + Br–(aq)
E) Br2(l) + Zn2+(aq) → Zn + 2Br–(aq)
65) What is E° of the spontaneous cell made from the Zn2+(aq)/Zn(s) (-0.76 V) and Br2(l)/2 Br–(aq) (1.07 V)
half cells?
A) -1.83 V
B) 0.31 V
C) 1.83 V
D) -0.31 V
E) -0.76 V
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66) Using the following reduction half-reactions and their respective standard reduction potentials at 25
°C, draw a diagram of a galvanic cell.
Cr2O72-(aq) + 14 H+(aq) + 6e– → 2 Cr3+(aq) + 7 H2O(l) E° = +1.33 V
Zn2+(aq) + 2 e– → Zn(s) E° = -0.763 V
A) Zn2+(aq) ∣ Zn(s), H+(aq) Cr2O72-(aq), Cr(s) ∣ Cr3+(aq)
B) Zn(s) ∣ Zn2+(aq) H+(aq), Cr3+(aq) ∣ Cr(s)
C) Cr(s) ∣ Cr3+(aq), H+(aq), Cr2O72-(aq) Zn(S) ∣ Zn2+(aq)
D) Zn(s) ∣ Zn2+(aq) Cr2O72-(aq), H+(aq), Cr3+(aq) ∣ Pt(s)
E) Pt(s) ∣ Cr3+(aq), Cr2O72-(aq), H+(aq) Zn2+(aq) ∣ Zn(s)
67) Which two of the following half-reactions will combine to give the galvanic cell with the highest cell
potential?
1) 2 H+(aq) + 2 e– → H2(g) E° = 0
2) Pb+2(aq) + 2 e– → Pb(s) E° = -0.125 V
3) I2(s) + 2 e– → 2 I–(aq) E° = +0.535 V
4) Zn+2(aq) + 2 e– → Zn(s) E° = -0.763 V
A) 1 and 4
B) 2 and 4
C) 3 and 4
D) 1 and 3
E) 2 and 3
68) What is E° of the spontaneous cell made from Ag+(aq)/Ag(s) (0.80 V) and Cl2(g)/Cl–(aq) (1.36 V) half
cells?
A) 2.16 V
B) -2.16 V
C) -0.56 V
D) 0.56 V
E) 1.36 V