Deck 18: Electrochemistry

Question 1

What is undergoing oxidation in the redox reaction represented by the following cell notation? Fe(s) ∣ Fe³⁺(aq) Cl₂(g) ∣ Cl⁻(aq) ∣ Pt(s)

A) Fe(s)
B) Fe³⁺(aq)
C) Cl₂(g)
D) Cl⁻(aq)
E) Pt(s)

Answer 1

Fe(s)

Question 2

Which of the following is the strongest reducing agent?

A) Al(s)
B) Zn(s)
C) Mg(s)
D) Al³⁺(aq)
E) Mg²⁺(aq)

Answer 2

Mg(s)

Question 3

Describe how water can be made to be a good conductor of electrical current.

A) use pure water
B) heat the water
C) add salt
D) chill the water
E) vaporize the water

Answer 3

add salt

Question 4

Determine the cell notation for the redox reaction given below: Sn(s) + 2Ag⁺(aq) → Sn²⁺(aq) + 2Ag(s)

A) Ag⁺(aq) ∣ Ag(s) Sn(s) ∣ Sn²⁺(aq)
B) Ag(s) ∣ Ag⁺(aq) Sn²⁺(aq) ∣ Sn(s)
C) Sn(s) ∣ Sn²⁺(aq) Ag⁺(aq) ∣ Ag(s)
D) Sn²⁺(aq) ∣ Sn(s) Ag(s) ∣ Ag⁺(aq)
E) Sn(s) ∣ Ag(s) Sn²⁺(aq) ∣ Ag⁺(aq)

Question 5

Which of the following is the strongest reducing agent?

A) Na(s)
B) Li⁺(aq)
C) Ca(s)
D) Ca²⁺(aq)
E) Li(s)

Question 6

Which of the following is the strongest reducing agent?

A) Sn²⁺(aq)
B) Cr³⁺(aq)
C) Sn⁴⁺(aq)
D) Cr(s)
E) Sn(s)

Question 7

Which of the following is TRUE about standard electrode potentials?

A) E°_cell ^{is negative for spontaneous reactions.}
B) Electrons will flow from a more positive electrode to a more negative electrode.
C) The electrode potential of the standard hydrogen electrode is exactly zero.
D) E°_cell is the sum between standard reduction potentials of the anode and the cathode.
E) The electrode in any half-cell with a greater tendency to undergo reduction is negatively charged relative to the standard hydrogen electrode and therefore has E° < 0.

Question 8

How many electrons are transferred in the following reaction? (The reaction is unbalanced.) I₂(s) + Fe(s) → Fe³⁺(aq) + I⁻(aq)

A) 1
B) 2
C) 6
D) 3
E) 4

Question 9

What is the oxidizing agent in the redox reaction represented by the following cell notation? Ni(s) ∣ Ni²⁺(aq) Ag⁺(aq) ∣ Ag(s)

A) Ni(s)
B) Ni²⁺(aq)
C) Ag⁺(aq)
D) Ag(s)
E) Pt(s)

Question 10

Determine the redox reaction represented by the following cell notation: Mg(s) ∣ Mg²⁺(aq) Cu²⁺(aq) ∣ Cu(s)

A) Cu(s) + Mg²⁺(aq) → Mg(s) + Cu²⁺(aq)
B) Mg(s) + Cu²⁺(aq) → Cu(s) + Mg²⁺(aq)
C) 2Mg(s) + Cu²⁺(aq) → Cu(s) + 2Mg²⁺(aq)
D) 2Cu(s) + Mg²⁺(aq) → Mg(s) + 2Cu²⁺(aq)
E) 3Mg(s) + 2Cu²⁺(aq) → 2Cu(s) + 3Mg²⁺(aq)

Question 11

Which of the following is the weakest oxidizing agent?

A) Sn²⁺(aq)
B) Cr³⁺(aq)
C) Sn⁴⁺(aq)
D) Cr(s)
E) Sn(s)

Question 12

What is undergoing reduction in the redox reaction represented by the following cell notation? Fe(s) ∣ Fe³⁺(aq) Cl₂(g) ∣ Cl⁻(aq) ∣ Pt(s)

A) Fe(s)
B) Fe³⁺(aq)
C) Cl₂(g)
D) Cl⁻(aq)
E) Pt(s)

Question 13

What is the reducing agent in the redox reaction represented by the following cell notation? Ni(s) ∣ Ni²⁺(aq) Ag⁺(aq) ∣ Ag(s)

A) Ni(s)
B) Ni²⁺(aq)
C) Ag⁺(aq)
D) Ag(s)
E) Pt(s)

Question 14

What is undergoing oxidation in the redox reaction represented by the following cell notation? Pb(s) ∣ Pb²⁺(aq) H⁺(aq) ∣ H₂(g) ∣ Pt(s)

A) H₂(g)
B) H⁺(aq)
C) Pb²⁺(aq)
D) Pb(s)
E) Pt(s)

Question 15

Determine the cell notation for the redox reaction given below: Pb(s) + 2H⁺(aq) → Pb²⁺(aq) + H₂(g)

A) H⁺(aq) ∣ H₂(g) ∣ Pt(s) Pb(s) ∣ Pb²⁺(aq)
B) H₂(g) ∣ H⁺(aq) ∣ Pt(s) Pb²⁺(aq) ∣ Pb(s)
C) Pb²⁺(aq) ∣ Pb(s) H₂(g) ∣ H⁺(aq) ∣ Pt(s)
D) Pb(s) ∣ Pb²⁺(aq) H⁺(aq) ∣ H₂(g) ∣ Pt(s)
E) Pb(s) ∣ H₂(g) Pb²⁺(aq) ∣ H⁺(aq) ∣ Pt(s)

Question 16

Determine the cell notation for the redox reaction given below: 3Cl₂(g) + 2Fe(s) → 6Cl⁻(aq) + 2Fe³⁺(aq)

A) Cl₂(g) ∣ Cl⁻(aq) ∣ Pt(s) Fe(s) ∣ Fe³⁺(aq)
B) Cl⁻(aq) ∣ Cl₂(g) ∣ Pt(s) Fe³⁺(aq) ∣ Fe(s)
C) Fe³⁺(aq) ∣ Fe(s) Cl⁻(aq) ∣ Cl₂(g) ∣ Pt(s)
D) Fe(s) ∣ Cl₂(g) Fe³⁺(aq) ∣ Cl⁻(aq) ∣ Pt(s)
E) Fe(s) ∣ Fe³⁺(aq) Cl₂(g) ∣ Cl⁻(aq) ∣ Pt(s)

Question 17

How many electrons are transferred in the following reaction? (The reaction is unbalanced.) Fe²⁺(aq) + K(s) → Fe(s) + K⁺(aq)

A) 1
B) 2
C) 3
D) 4
E) 6

Question 18

What is the oxidizing agent in the redox reaction represented by the following cell notation? Sn(s) ∣ Sn²⁺(aq) Ag⁺(aq) ∣ Ag(s)

A) Sn(s)
B) Ag⁺(aq)
C) Sn²⁺(aq)
D) Ag(s)
E) Pt(s)

Question 19

What is the reducing agent in the redox reaction represented by the following cell notation? Sn(s) ∣ Sn²⁺(aq) Ag⁺(aq) ∣ Ag(s)

A) Sn(s)
B) Ag⁺(aq)
C) Sn²⁺(aq)
D) Ag(s)
E) Pt(s)

Question 20

What is undergoing reduction in the redox reaction represented by the following cell notation? Pb(s) ∣ Pb²⁺(aq) H⁺(aq) ∣ H₂(g) ∣ Pt(s)

A) H₂(g)
B) H⁺(aq)
C) Pb²⁺(aq)
D) Pb(s)
E) Pt(s)

Question 21

Which of the following is the weakest oxidizing agent?

A) Cl₂(g)
B) Au⁺³(aq)
C) F₂(g)
D) O₂(g)
E) Br₂(l)

Question 22

Which of the following is the weakest oxidizing agent?

A) H₂O₂(aq)
B) Fe³⁺(aq)
C) ClO₂(g)
D) I₂(s)
E) Fe(s)

Question 23

Use the standard half-cell potentials listed below to calculate the standard cell potential for the following reaction occurring in an electrochemical cell at 25 °C. (The equation is balanced.) 2K(s) + I₂(s) → 2K⁺(aq) + 2I⁻(aq)
K⁺(aq) + e⁻ → K (s) E° = -2.93 V
I₂(s) + 2 e⁻ → 2 I⁻(aq) E° = +0.54 V

A) +6.40 V
B) +1.85 V
C) -5.32 V
D) +3.47 V
E) +5.32 V

Question 24

Which of the following is the strongest oxidizing agent?

A) Cl₂(g)
B) Au⁺³(aq)
C) F₂(g)
D) O₂(g)
E) Fe(s)

Question 25

Which of the following is the weakest reducing agent?

A) Br₂(l)
B) Au³⁺(aq)
C) Ag(s)
D) Br⁻(aq)
E) Au(s)

Question 26

Use the standard half-cell potentials listed below to calculate the standard cell potential for the following reaction occurring in an electrochemical cell at 25 °C. (The equation is balanced.) 3Cl₂(g) + 2Fe(s) → 6Cl⁻(aq) + 2Fe³⁺(aq)
Cl₂(g) + 2 e⁻ → 2Cl⁻(aq) E° = +1.36 V
Fe³⁺(aq) + 3 e⁻ → Fe(s) E° = -0.04 V

A) +4.16 V
B) -1.40 V
C) -1.32 V
D) +1.32 V
E) +1.40 V

Question 27

Use the standard half-cell potentials listed below to calculate the standard cell potential for the following reaction occurring in an electrochemical cell at 25 °C. (The equation is balanced.) 2 Ag⁺(aq) + Pb(s) → 2Ag(s) + Pb²⁺(aq)
Ag⁺(aq) + e- → Ag(s) E°= 0.80 V
Pb²⁺(aq) + 2 e- → Pb(s) E°= -0.13 V

A) +0.93 V
B) +1.85 V
C) -5.32 V
D) +5.47 V
E) +0.67 V

Question 28

Use the standard half-cell potentials listed below to calculate the standard cell potential for the following reaction occurring in an electrochemical cell at 25°C. (The equation is balanced.) Br₂(l) + 2Cl^-(aq) → 2Br^-(aq) + Cl₂ (g)
Br₂(l) + 2 e → 2Br^-(aq) E°= 1.09 V
2Cl^- (aq) → Cl₂(g) + 2 e ^{- E}°= -1.36 V

A) +0.93 V
B) +2.24 V
C) +2.45 V
D) +5.47 V
E) +0.67 V

Question 29

Which of the following reactions would be the most spontaneous at 298 K?

A) A + 2 B → C; E°_cell = +0.98 V
B) A + B → 2 C; E°_cell = -0.030 V
C) A + B → 3 C; E°_cell = +0.15 V
D) A + B → C; E°_cell = +1.22 V
E) A + B → C; E°_cell = -1.22 V

Question 30

Use the standard half-cell potentials listed below to calculate the standard cell potential for the following reaction occurring in an electrochemical cell at 2 5°C. (The equation is balanced.) Pb(s) + Br₂(l) → Pb²⁺(aq) + 2 Br⁻(aq)
Pb²⁺(aq) + 2 e⁻ → Pb(s) E° = -0.13 V
Br₂(l) + 2 e⁻ → 2 Br⁻(aq) E° = +1.07 V

A) +1.20 V
B) +0.94 V
C) -0.94 V
D) -1.20 V
E) -0.60 V

Question 31

Use the standard half-cell potentials listed below to calculate the standard cell potential for the following reaction occurring in an electrochemical cell at 25°C. (The equation is balanced.) Pb²⁺(aq) + Mg(s) → Pb(s) + Mg²⁺(aq)
Mg²⁺(aq) +2 e- →Mg(s) E°= -2.37 V
Pb²⁺(aq) + 2e- → Pb(s) E°= -0.13 V

A) +0.93 V
B) +2.24 V
C) -5.32 V
D) +5.47 V
E) +0.67 V

Question 32

Which of the following is the strongest oxidizing agent?

A) H₂O₂(aq)
B) Fe³⁺(aq)
C) ClO₂(g)
D) I₂(s)
E) Fe(s)

Question 33

Use the standard half-cell potentials listed below to calculate the standard cell potential for the following reaction occurring in an electrochemical cell at 25 °C. (The equation is balanced.) Sn(s) + 2Ag⁺(aq) → Sn²⁺(aq) + 2Ag(s)
Sn²⁺(aq) + 2 e⁻ → Sn(s) E° = -0.14 V
Ag⁺(aq) + e⁻ → Ag(s) E° = +0.80 V

A) +1.74 V
B) +0.94 V
C) +1.08 V
D) -1.08 V
E) -1.74 V

Question 34

Determine which of the following pairs of reactants will result in a spontaneous reaction at 25 °C.

A) Pb²⁺(aq) + Cu(s); if E°(Pb²⁺/Pb) = -0.13V and E°(Cu²⁺/Cu) = +0.16V
B) Ag⁺(aq) + Br⁻(aq); if E°(Ag⁺/Ag) = 0.80V and E°(Br₂/Br^-) = +1.09V
C) Li⁺(aq) + Al(s); if E°(Li⁺/Li) = -3.04V and E°(Al³⁺/Al) = -1.66V
D) Fe³⁺(aq) + Ni(s); if E°(Fe³⁺/Fe) = -0.04V and E°(Ni²⁺/Ni) = -0.23V
E) Cd²⁺(aq) + I^-(aq); if E°(Cd²⁺/Cd) = -0.40V and E°(I₂/I^-) = + 0.54V

Question 35

Which of the following is the strongest oxidizing agent?

A) MnO₂(s)
B) Cl⁻(aq)
C) Cu⁺(aq)
D) SO₄^2-(aq)
E) MnO₄⁻(aq)

Question 36

Which of the following statements is true for the cell diagram below? Zn(s) ∣ Zn²⁺(aq) Cu²⁺(aq) ∣ Cu(s)

A) Zn is oxidized, Cu is reduced; the single vertical lines represent phase boundaries while the two vertical lines represent a salt bridge.
B) Zn²⁺is oxidized, Cu is reduced; the single vertical lines represent phase boundaries while the two vertical lines represent a salt bridge.
C) Zn is oxidized, Cu²⁺ is reduced; the single vertical lines represent phase boundaries while the two vertical lines represent a salt bridge.
D) Zn is oxidized, Cu²⁺ is reduced; the single vertical lines represent salt bridges while the two vertical lines represent a phase boundary.
E) Zn is reduced, Cu²⁺ is oxidized; the single vertical lines represent phase boundaries while the two vertical lines represent a salt bridge.

Question 37

Use the standard half-cell potentials listed below to calculate the standard cell potential for the following reaction occurring in an electrochemical cell at 25 °C. (The equation is balanced.) Mg(s) + Cu²⁺(aq) → Cu(s) + Mg²⁺(aq)
Mg²⁺(aq) + 2 e⁻ → Mg(s) E° = -2.38 V
Cu²⁺(aq) + 2 e⁻ → Cu(s) E° = +0.34 V

A) +2.04 V
B) -2.04 V
C) +2.72 V
D) -1.36 V
E) +1.36 V

Question 38

Which of the following is the weakest reducing agent?

A) Cl₂(g)
B) Au⁺³ (aq)
C) F₂(g)
D) O₂(g)
E) Fe(s)

Question 39

Which of the following is the strongest oxidizing agent?

A) Al(s)
B) Zn²⁺(aq)
C) Mg(s)
D) Al³⁺(aq)
E) Mg²⁺(aq)

Question 40

Which of the following is the strongest oxidizing agent?

A) Br₂(l)
B) Au³⁺(aq)
C) Ag(s)
D) Br⁻(aq)
E) Au(s)

Question 41

Use the provided reduction potentials to calculate the equilibrium constant (K) for the following balanced redox reaction at 25 °C: 2Al(s) + 3Mg²⁺(aq) → 2Al³⁺(aq) + 3Mg(s)
E°(Al³⁺/Al) = -1.66 V and E°(Mg²⁺/Mg) = -2.37 V

A) 1.1 × 10⁷²
B) 8.9 × 10^-70
C) 9.7 × 10^-73
D) 1.0 × 10²⁴
E) 4.6 × 10³¹

Question 42

Use the provided reduction potentials to calculate Δ_rG° for the following redox reaction: 2Al(s) + 3Mg²⁺(aq) → 2Al³⁺(aq) + 3Mg(s)
E°(Al³⁺/Al) = -1.66 V and E°(Mg²⁺/Mg) = -2.37 V

A) +4.1 × 10² kJ mol^-1
B) +1.4 × 10² kJ mol^-1
C) -2.3 × 10² kJ mol^-1
D) -7.8 × 10² kJ mol^-1
E) +6.8 × 10² kJ mol^-1

Question 43

Calculate the cell potential for the following unbalanced reaction that takes place in an electrochemical cell at 25 °C when [ ] = 0.945 M and [ ] = 1.37 M Zn(s) + (aq) → (aq) + Cr(s)
E°(Zn²⁺/Zn) = -0.76 V and E°(Cr³⁺/Cr) = -0.73 V

A) +0.03 V
B) -0.03 V
C) -1.18 V
D) +1.18 V
E) +0.49 V

Question 44

Calculate the cell potential for the following unbalanced reaction that takes place in an electrochemical cell at 25 °C when [ ] = 0.914 M and [ ] = 0.0230 M Mg(s) + (aq) → (aq) + Fe(s)
E°(Mg²⁺/Mg) = -2.37 V and E°(Fe³⁺/Fe) = -0.036 V

A) +2.32 V
B) +2.30 V
C) -2.32 V
D) -2.30 V
E) +1.23 V

Question 45

Which of the following metals will dissolve in HCl?

A) Au; E°(Au³⁺/Au) = +1.50V
B) Ag; E°(Ag⁺/Ag) = +0.80V
C) Cu; E°(Cu²⁺/Cu) = +0.34V
D) Al; E°(Al³⁺/Al) = -1.66V
E) Pt; E°(Pt²⁺/Pt) = +1.19V

Question 46

Determine which of the following pairs of reactants will result in a spontaneous reaction at 25 °C.

A) Sn⁴⁺(aq) + Mg(s); if E°(Sn⁴⁺/Sn²⁺) = +0.15V and E°(Mg²⁺/Mg) = -2.37V
B) Cr³⁺(aq) + Ni(s); if E°(Cr³⁺/Cr) = -0.73V and E°(Ni²⁺/Ni) = -0.23V
C) Zn(s) + Na⁺(aq); if E°(Zn²⁺/Zn) = -0.76V and E°(Na⁺/Na) = -2.71V
D) Fe(s) + Ba²⁺(aq); if E°(Fe³⁺/Fe) = -0.04V and E°(Ba²⁺/Ba) = -2.90V
E) Ni²⁺(aq) + NO(g); if E°(Ni²⁺/Ni) = -0.23V and E°(NO₃^-/NO) = +0.96V

Question 47

If the standard reduction potential of Zn is -0.76 V, which of the following statements about a cell whose half-cells are Zn²⁺/Zn and SHE is correct?

A) SHE will be the cell's cathode, Zn(s) will be the cell's anode, and the measured cell potential will be 0.76 V.
B) SHE will be the cell's anode, Zn(s) will be the cell's cathode, and the measured cell potential will be 0.76 V.
C) SHE will be the cell's cathode, Zn(s) will be the cell's anode, and the measured cell potential will be -0.76 V.
D) SHE will be the cell's cathode, Zn²⁺(aq) will be the cell's anode, and the measured cell potential will be 0.76 V.
E) H⁺(aq) will be the cell's cathode, Zn²⁺(aq) will be the cell's anode, and the measured cell potential will be 0.76 V.

Question 48

Calculate the cell potential for the following unbalanced reaction that takes place in an electrochemical cell at 25 °C when [ ] = 2.00 M and [ ] = 0.00300 M Zn(s) + (aq) → (aq) + Cr(s)
E°(Zn²⁺/Zn) = -0.76 V and E°(Cr³⁺/Cr) = -0.73 V

A) +0.06 V
B) -0.19 V
C) +1.30 V
D) +0.02 V
E) +0.11 V

Question 49

Calculate the cell potential for the following unbalanced reaction that takes place in an electrochemical cell at 25 °C when [ ] = 3.20 M and [ ] = 0.000100 M Mg(s) + (aq) → (aq) + Fe(s)
E°(Mg²⁺/Mg) = -2.37 V and E°(Fe³⁺/Fe) = -0.036 V

A) -2.24 V
B) +2.24 V
C) +1.24 V
D) -1.24 V
E) +2.14 V

Question 50

Use the tabulated half-cell potentials to calculate the equilibrium constant (K) for the following balanced redox reaction at 25 °C: 3I₂(s) + 2Fe(s) → 2Fe³⁺(aq) + 6I⁻(aq)
E°(I₂/I^-) = + 0.54 V and E°(Fe³⁺/Fe) = -0.036 V

A) 3.5 × 10^-59
B) 1.1 × 10¹⁷
C) 2.4 × 10⁵⁸
D) 8.9 × 10^-18
E) 1.7 × 10²⁹

Question 51

Identify the characteristics of a spontaneous reaction.

A) Δ_rG° > 0
B) ΔE°_cell < 0
C) K < 0
D) ΔE°_cell > 0
E) K = 0

Question 52

Which of the following metals will dissolve in nitric acid but not hydrochloric acid?

A) Fe; E°(Fe²⁺/Fe) = -0.45V
B) Pb; E°(Pb²⁺/Pb) = -0.13V
C) Cu; E°(Cu²⁺/Cu) = +0.34V
D) Sn; E°(Sn²⁺/Sn) = -0.14V
E) Ni; E°(Ni²⁺/Ni) = -0.23V

Question 53

Use the provided reduction potentials to calculate Δ_rG° for the following balanced redox reaction: 3I₂(s) + 2Fe(s) → 2Fe³⁺(aq) + 6I⁻(aq)
E°(I₂/I^-) = + 0.54 V and E°(Fe³⁺/Fe) = -0.036 V

A) -1.1 × 10² kJ mol^-1
B) +4.9 × 10¹ kJ mol^-1
C) -9.7 × 10¹ kJ mol^-1
D) +2.3 × 10² kJ mol^-1
E) -3.3 × 10² kJ mol^-1

Question 54

Which of the following metals will dissolve in nitric acid but not hydrochloric acid?

A) Cd; E°(Cd²⁺/Cd) = -0.40V
B) Cr; E°(Cr³⁺/Cr) = -0.73V
C) Mn; E°(Mn²⁺/Mn) = -1.18V
D) Ag; E°(Ag⁺/Ag) = +0.80V
E) Al; E°(Al³⁺/Al) = -1.66V

Question 55

Calculate the cell potential for the following unbalanced reaction that takes place in an electrochemical cell at 25 °C when [ ] = 0.500 M and [ ] = 2.00 M Mg(s) + (aq) → (aq) + Fe(s)
E°(Mg²⁺/Mg) = -2.37 V and E°(Fe³⁺/Fe) = -0.036 V

A) +2.09 V
B) -3.18 V
C) +2.35 V
D) +0.36 V
E) -1.51 V

Question 56

Calculate the cell potential for the following unbalanced reaction that takes place in an electrochemical cell at 25 °C when [ ] = 0.000612 M and [ ] = 1.29 M Mg(s) + (aq) → (aq) + Fe(s)
E°(Mg²⁺/Mg) = -2.37 V and E°(Fe³⁺/Fe) = -0.036 V

A) -3.42 V
B) +3.42 V
C) -4.32 V
D) +2.43 V
E) +3.24 V

Question 57

Which of the following reactions would have the smallest value of K at 298 K?

A) A + B → C; E°_cell = +1.22 V
B) A + 2 B → C; E°_cell = +0.98 V
C) A + B → 2 C; E°_cell = -0.030 V
D) A + B → 3 C; E°_cell = +0.15 V
E) A + B → C; E°_cell = -0.015 V

Question 58

Use the tabulated half-cell potentials to calculate the equilibrium constant (K) for the following balanced redox reaction at 25 °C: Pb²⁺(aq) + Cu(s) → Pb(s) + Cu²⁺(aq)
E°(Pb²⁺/Pb) = -0.13 V and E°(Cu²⁺/Cu) = +0.34 V

A) 7.9 × 10^-8
B) 8.9 × 10⁷
C) 7.9 × 10¹⁵
D) 1.3 × 10^-16
E) 1.1 × 10^-8

Question 59

Determine which of the following pairs of reactants will result in a spontaneous reaction at 25 °C.

A) I^-(aq) + Zn²⁺(aq); if E°(I₂/I^-) = + 0.54V and E°(Zn²⁺/Zn) = -0.76V
B) Ca(s) + Mg²⁺(aq); if E°(Ca²⁺/Ca) = -2.76V and E°(Mg²⁺/Mg) = -2.37V
C) H₂(g) + Cd²⁺(aq); if E°(Cd²⁺/Cd) = -0.40V
D) Ag(s) + Sn²⁺(aq); if E°(Ag⁺/Ag) = + 0.80V and E°(Sn²⁺/Sn) = -0.14V
E) Ag⁺(aq) + Mn²⁺(aq); if E°(Ag⁺/Ag) = + 0.80V and E°(MnO₄^-/Mn²⁺) = +1.51V

Question 60

Use the provided reduction potentials to calculate Δ_rG° for the following balanced redox reaction: Pb²⁺(aq) + Cu(s) → Pb(s) + Cu²⁺(aq)
E°(Pb²⁺/Pb) = -0.13 V and E°(Cu²⁺/Cu) = +0.34 V

A) -41 kJ mol^-1
B) -0.47 kJ mol^-1
C) +46 kJ mol^-1
D) +91 kJ mol^-1
E) -21 kJ mol^-1

Question 61

Predict the species that will be reduced first if a mixture of molten salts containing the following ions undergoes electrolysis: Zn²⁺, Fe³⁺, Mg²⁺, Br^-, I^-

A) Zn²⁺
B) Mg²⁺
C) Br^-
D) Fe³⁺
E) I^-

Question 62

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25 °C: Sn(s) ∣ Sn²⁺(aq, 0.022 mol L^-1) Ag⁺(aq, 2.7 mol L^-1) ∣ Ag(s)
E°(Sn²⁺/Sn) = -0.14 V and E°(Ag⁺/Ag) = +0.80 V

A) +1.01 V
B) -0.83 V
C) +1.31 V
D) +0.01 V
E) -0.66 V

Question 63

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25 °C: Mg(s) ∣ Mg²⁺(aq, 2.74 mol L^-1) Cu²⁺(aq, 0.0033 mol L^-1) ∣ Cu(s)
E°(Mg²⁺/Mg) = -2.37 V and E°(Cu²⁺/Cu) = +0.34 V

A) -2.80 V
B) +2.62 V
C) +2.71 V
D) +2.12 V
E) -1.94 V

Question 64

What is the reaction at the anode in a breathalyzer?

A) Ethanol is oxidized to acetic acid.
B) Acetic acid is reduced to ethanol.
C) Oxygen is reduced.
D) Hydrogen is oxidized.
E) Ethanol is oxidized to acetaldehyde.

Question 65

Predict the species that will be reduced first if a mixture of molten salts containing the following ions undergoes electrolysis: Zn²⁺, Mn²⁺, Na⁺, Al³⁺, Li⁺

A) Na⁺
B) Zn²⁺
C) Mn²⁺
D) Al³⁺
E) Li⁺

Question 66

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25 °C: Sn(s) ∣ Sn²⁺(aq, 0.010 mol L^-1) Ag⁺(aq, 1.00 mol L^-1) ∣ Ag(s)
E°(Sn²⁺/Sn) = -0.14 V and E°(Ag⁺/Ag) = +0.80 V

A) +1.18 V
B) -1.18 V
C) +1.00 V
D) +0.94 V
E) -0.94 V

Question 67

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25 °C: Al(s) ∣ Al³⁺(aq, 0.115 mol L^-1) Al³⁺(aq, 3.89 mol L^-1) ∣ Al(s)
E°(Al³⁺/Al) = -1.66 V

A) +1.66 V
B) +0.060 V
C) 0.00 V
D) +0.090 V
E) +0.030 V

Question 68

Calculate the cell potential for the following unbalanced reaction that takes place in an electrochemical cell at 25 °C when [ ] = 1.10 M and [ ] = 1.10 M Mg(s) + (aq) → (aq) + Fe(s)
E°(Mg²⁺/Mg) = -2.37 V and E°(Fe³⁺/Fe) = -0.036 V

A) +2.33 V
B) -3.23 V
C) +1.48 V
D) +2.22 V
E) +0.68 V

Question 69

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25 °: Cu(s) ∣ Cu²⁺(aq, 0.0032 mol L^-1) Cu²⁺(aq, 4.48 mol L^-1) ∣ Cu(s)
E°(Cu²⁺/Cu) = +0.34 V

A) 0.00 V
B) +0.093 V
C) +0.34 V
D) +0.186 V
E) +0.052 V

Question 70

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25 °C: Sn(s) ∣ Sn²⁺(aq, 0.100 mol L^-1) Ag⁺(aq, 0.200 mol L^-1) ∣ Ag(s)
E°(Sn²⁺/Sn) = -0.14 V and E°(Ag⁺/Ag) = +0.80 V

A) -2.68 V
B) -0.03 V
C) +0.95 V
D) +0.93 V
E) +2.10 V

Question 71

Identify the battery that is used as a common flashlight battery.

A) dry-cell battery
B) lithium-ion battery
C) lead-acid storage battery
D) NiCad battery
E) fuel cell

Question 72

What is the reaction at the cathode in a breathalyzer?

A) Ethanol is oxidized to acetic acid.
B) Acetic acid is reduced to ethanol.
C) Oxygen is reduced.
D) Hydrogen is oxidized.
E) Ethanol is oxidized to acetaldehyde.

Question 73

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25 °C: Sn(s) ∣ Sn²⁺(aq, 1.8 mol L^-1) Ag⁺(aq, 0.055 mol L^-1) ∣ Ag(s)
E°(Sn²⁺/Sn) = -0.14 V and E°(Ag⁺/Ag) = +0.80 V

A) -0.94 V
B) -0.85 V
C) +1.02 V
D) +0.98 V
E) +0.86 V

Question 74

Identify the battery type that has a high overcharge tolerance.

A) NiCad battery
B) lithium-ion battery
C) nickel-metal hydride battery
D) lead-acid storage battery
E) zinc-manganese battery

Question 75

Identify the battery that is in most automobiles.

A) dry-cell battery
B) lithium-ion battery
C) lead-acid storage battery
D) NiCad battery
E) fuel cell

Question 76

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25 °: Fe(s) ∣ Fe³⁺(aq, 0.0011 mol L^-1) Fe³⁺(aq, 2.33 mol L^-1) ∣ Fe(s)
E°(Fe³⁺/Fe) = -0.036 V

A) +0.066 V
B) -0.036 V
C) 0.00 V
D) -0.099 V
E) +0.20 V

Question 77

Predict the species that will be reduced first if a mixture of molten salts containing the following ions undergoes electrolysis: Cd²⁺, Ni²⁺, Sn²⁺, Al³⁺, Pb²⁺

A) Pb²⁺
B) Al³⁺
C) Sn²⁺
D) Ni²⁺
E) Cd²⁺

Question 78

Predict the species that will be reduced first if a mixture of molten salts containing the following ions undergoes electrolysis: Cu²⁺, Ag⁺, Sn⁴⁺, Fe³⁺, Au³⁺

A) Cu²⁺
B) Ag⁺
C) Sn⁴⁺
D) Fe³⁺
E) Au³⁺

Question 79

Identify the components of a fuel cell.

A) nickel-metal hydride
B) lithium-ion
C) hydrogen-oxygen
D) nickel-cadmium
E) zinc-manganese

Question 80

Predict the species that will be reduced first if a mixture of molten salts containing the following ions undergoes electrolysis: Na⁺, Ca²⁺, Cl⁻, Br⁻, F⁻

A) Na⁺
B) Cl⁻
C) Ca²⁺
D) Br⁻
E) F⁻