Ch21 Electrochemistry Chemical Change And Exam Prep

Chapter 21 Test Bank

Electrochemistry: Chemical Change and Electrical Work

1. Which one of the following is not a redox reaction?

A. Al(OH)₄(aq) + 4H(aq) → Al³+(aq) + 4H₂O(l)

B. C₆H₁₂O₆(s) + 6O₂(g) → 6CO₂(g) + 6H₂O(l)

C. Na₆FeCl₈(s) + 2Na(l) → 8NaCl(s) + Fe(s)

D. 2H₂O₂(aq) → 2H₂O(l) + O₂(g)

E. CO₂(g) + H₂(g) → CO(g) + H₂O(g)

Accessibility: Keyboard Navigation

Bloom's: 2. Understand

Difficulty: Easy

Gradable: automatic

Subtopic: Oxidation-Reduction (REDOX) Reactions (Definition and Balancing)

Topic: Electrochemistry

2. Consider the reaction

CuO(s) + H₂(g) → Cu(s) + H₂O(l)

In this reaction, which substances are the oxidant and reductant, respectively?

A. CuO and H₂

B. H₂ and CuO

C. CuO and Cu

D. H₂O and H₂

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Easy

Gradable: automatic

Subtopic: Oxidation-Reduction (REDOX) Reactions (Definition and Balancing)

Topic: Electrochemistry

3. Consider the following balanced redox reaction

Mn²+(aq) + S₂O8^2–(aq) + 2H₂O(l) → MnO₂(s) + 4H(aq) + 2SO₄^2–(aq)

Which of the following statements is true?

A. Mn²⁺(aq) is the oxidizing agent and is reduced.

B. Mn²⁺(aq) is the oxidizing agent and is oxidized.

C. Mn²⁺(aq) is the reducing agent and is oxidized.

D. Mn²⁺(aq) is the reducing agent and is reduced.

E. Manganese does not change its oxidation number in this reaction.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Easy

Gradable: automatic

Subtopic: Oxidation-Reduction (REDOX) Reactions (Definition and Balancing)

Topic: Electrochemistry

4. Consider the following balanced redox reaction

3CuO(s) + 2NH₃(aq) → N₂(g) + 3H₂O(l) + 3Cu(s)

Which of the following statements is true?

A. CuO(s) is the oxidizing agent and copper is reduced.

B. CuO(s) is the oxidizing agent and copper is oxidized.

C. CuO(s) is the reducing agent and copper is oxidized.

D. CuO(s) is the reducing agent and copper is reduced.

E. CuO(s) is the oxidizing agent and N₂(g) is the reducing agent.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Easy

Gradable: automatic

Subtopic: Oxidation-Reduction (REDOX) Reactions (Definition and Balancing)

Topic: Electrochemistry

5. When the following redox equation is balanced with smallest whole number coefficients, the coefficient for nitrogen dioxide will be——.

I₂(s) + HNO₃(aq) → HIO₃(aq) + NO₂(g) + H₂O(l)

A. 1

B. 2

C. 4

D. 10

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Oxidation-Reduction (REDOX) Reactions (Definition and Balancing)

Topic: Electrochemistry

6. When the following redox equation is balanced with smallest whole number coefficients, the coefficient for the hydrogen sulfate ion will be

Al(s) + HSO₄(aq) + OH_–(aq) → Al₂O₃(s) + S_2–(aq) + H₂O(l)

A. 1.

B. 3.

C. 4.

D. 8.

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Oxidation-Reduction (REDOX) Reactions (Definition and Balancing)

Topic: Electrochemistry

7. When the following redox equation is balanced with smallest whole number coefficients, the coefficient for zinc will be

Zn(s) + ReO₄(aq) → Re(s) + Zn₂₊(aq) (acidic solution)

A. 2.

B. 7.

C. 8.

D. 16.

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Oxidation-Reduction (REDOX) Reactions (Definition and Balancing)

Topic: Electrochemistry

8. When the following redox equation is balanced with smallest whole number coefficients, the coefficient for the iodide ion will be

I–(aq) + NO₃–(aq) → NO(g) + I₂(s) (acidic solution)

A. 2.

B. 3.

C. 6.

D. 8.

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Oxidation-Reduction (REDOX) Reactions (Definition and Balancing)

Topic: Electrochemistry

9. When the following redox equation is balanced with smallest whole number coefficients, the coefficient for Sn(OH)3–will be

Bi(OH)₃(s) + Sn(OH)₃(aq) → Sn(OH)₆^2–(aq) + Bi(s) (basic solution)

A. 1.

B. 2.

C. 3.

D. 6.

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Oxidation-Reduction (REDOX) Reactions (Definition and Balancing)

Topic: Electrochemistry

10. Consider the following redox equation

Mn(OH)₂(s) + MnO₄(aq) → MnO₄^2–(aq) (basic solution)

When the equation is balanced with smallest whole number coefficients, what is the coefficient for OH^–(aq) and on which side of the equation is OH^–(aq) present?

A. 4, reactant side

B. 4, product side

C. 6, reactant side

D. 6, product side

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Oxidation-Reduction (REDOX) Reactions (Definition and Balancing)

Topic: Electrochemistry

11. Which of the following statements about voltaic and electrolytic cells is correct?

A. The electrons in the external wire flow from cathode to anode in both types of cell.

B. Oxidation occurs at the cathode only in a voltaic cell.

C. The free energy change, ΔG, is negative for an electrolytic cell.

D. The cathode is labeled as positive (+) in a voltaic cell but negative (–) in an electrolytic cell.

E. Reduction occurs at the anode in an electrolytic cell.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

12. Which of the following statements about voltaic and electrolytic cells is correct?

A. The anode will definitely gain weight in a voltaic cell.

B. Oxidation occurs at the cathode of both cells.

C. The free energy change, ΔG, is negative for the voltaic cell.

D. The electrons in the external wire flow from cathode to anode in an electrolytic cell.

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

13. Which one of the following pairs of substances could be used to construct a single redox electrode (i.e., they have an element in common, but in different oxidation states)?

A. HCl and Cl–

B. H+ and OH–

C. H₂O and H⁺

D. Fe³⁺ and Fe₂O₃

E. MnO₂ and Mn²⁺

Accessibility: Keyboard Navigation

Bloom's: 2. Understand

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

14. Which one of the following statements about electrochemical cells is correct?

A. In a salt bridge, current is carried by cations moving toward the anode, and anions toward the cathode.

B. In the external wire, electrons travel from cathode to anode.

C. The anode of a voltaic cell is labeled minus (–).

D. Oxidation occurs at the cathode, in an electrolytic cell.

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

15. Which of the following solids is commonly used as an inactive electrode in electrochemical cells?

A. zinc

B. graphite

C. copper

D. iron

E. sodium

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Easy

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

16. Which component of the following cell notation is the anode?

P | || R | S

A. P

B.

C. R

D. S

E. One of the | symbols is the anode.

Bloom's: 2. Understand

Difficulty: Easy

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

17. A voltaic cell is prepared using copper and silver. Its cell notation is shown below.

Cu(s) | Cu²⁺(aq) || Ag⁺(aq) | Ag(s)

Which of the following processes occurs at the cathode?

A. Cu(s) → Cu²⁺(aq) + 2e^–

B. Cu²⁺(aq) + 2e^– → Cu(s)

C. Ag(s) → Ag⁺(aq) + e^–

D. Ag⁺(aq) + e^– → Ag(s)

E. Cu(s) + 2Ag⁺(aq) → Cu²⁺(aq) + 2Ag(s)

Accessibility: Keyboard Navigation

Bloom's: 2. Understand

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

18. A voltaic cell prepared using aluminum and nickel has the following cell notation.

Al(s) | Al₃₊(aq) || Ni₂₊(aq) | Ni(s)

Which of the following reactions occurs at the anode?

A. Al(s) → Al³⁺(aq) + 3e^–

B. Al³⁺(aq) + 3e → Al(s)

C. Ni(s) → Ni²⁺(aq) + 2e^–

D. Ni²⁺(aq) + 2e^– → Ni(s)

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 2. Understand

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

19. A voltaic cell prepared using aluminum and nickel has the following cell notation.

Al(s) | Al³⁺(aq) || Ni²⁺(aq) | Ni(s)

Which of the following represents the correctly balanced spontaneous reaction equation for the cell?

A. Ni²⁺(aq) + Al(s) → Al³⁺(aq) + Ni(s)

B. 3Ni²⁺(aq) + 2Al(s) → 2Al³⁺(aq) + 3Ni(s)

C. Ni(s) + Al³⁺(aq) → Ni²⁺(aq) + Al(s)

D. 3Ni(s) + 2Al³⁺(aq) → 3Ni²⁺(aq) + 2Al(s)

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

20. A voltaic cell prepared using zinc and iodine has the following cell notation.

Zn(s) | Zn²₊(aq) || I^–(aq) | I₂(s) | C(graphite)

Which of the following equations correctly represents the balanced, spontaneous, cell reaction?

A. 2I^–(aq) + Zn²⁺(aq) → I₂(s) + Zn(s)

B. I₂(s) + Zn(s) → 2I^–(aq) + Zn²⁺(aq)

C. 2I^–(aq) + Zn(s) → I₂(s) + Zn²⁺(aq)

D. I₂(s) + Zn²⁺(aq) → 2I^–(aq) + Zn(s)

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

21. The line notation, Al(s) | Al³⁺(aq) || Co²⁺(aq) | Co(s), indicates that

A. Co is the reducing agent.

B. Co²⁺ ions are oxidized.

C. Al is the reducing agent.

D. Al³⁺ is the reducing agent.

E. aluminum metal is the cathode.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

22. The line notation, Pt | H₂(g) | H⁺(aq) || Cu²⁺(aq) | Cu(s), indicates that

A. copper metal is a product of the cell reaction.

B. hydrogen gas (H₂) is a product of the cell reaction.

C. Cu is the anode.

D. Pt is the cathode.

E. Cu²⁺ is the reducing agent.

Accessibility: Keyboard Navigation

Bloom's: 2. Understand

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

23. A voltaic cell can be prepared from copper and tin. What is the E°_cell for the cell that forms from the following half-reactions?

Cu²⁺(aq) + 2e– Cu(s) E° = 0.34 V

Sn⁴⁺(aq) + 2e– Sn²⁺(aq) E° = 0.13 V

A. 0.47 V

B. 0.21 V

C. –0.21 V

D. –0.47 V

E. 0.42 V

Bloom's: 3. Apply

Difficulty: Easy

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

24. What is the E°_cell for the cell represented by the combination of the following half-reactions?

2Hg²⁺(aq) + 2e– Hg₂²⁺(aq) E° = 0.92 V

Cr³⁺(aq) + 3e– Cr(s) E° = –0.74 V

A. –0.18 V

B. 0.18 V

C. 1.28 V

D. 1.66 V

E. 2.12 V

Bloom's: 3. Apply

Difficulty: Easy

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

25. What is the E°_cell for the cell represented by the combination of the following half-reactions?

ClO₄(aq) + 8H(aq) + 8e Cl–(aq) + 4H₂O(l) E° = 1.389 V

VO₂(aq) + 2H(aq) + e^– jVO(aq) + H₂O(l) E° = 0.991 V

A. –0.398 V

B. –2.380 V

C. 0.398 V

D. 2.380 V

E. None of these choices are correct.

Bloom's: 3. Apply

Difficulty: Easy

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

26. The redox reaction of peroxydisulfate with iodide has been used for many years as part of the iodine clock reaction which introduces students to kinetics. If E°_cell = 1.587 V and E° of the cathode half-cell is 0.536 V, what is E° of the anode half-cell?

S₂O₈^2–(aq) + 2H⁺ + 2I^–(aq) → 2HSO₄^–(aq) + I₂(aq)

A. –1.051 V

B. –2.123 V

C. 1.051 V

D. 2.123 V

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

27. The voltaic cell made up of cobalt, copper, and their M²⁺ ions, has E°_cell = 0.62 V. If E° of the cathode half-cell is 0.34 V, what is E° of the anode half-cell?

Cu²⁺(aq) + Co(s) → Cu(s) + Co²⁺(aq)

A. –0.28 V

B. –0.96 V

C. 0.28 V

D. 0.96 V

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

28. A voltaic cell has a standard cell potential equal to 0.74 V. If the standard electrode (reduction) potential for the anode is –0.22 V, what is the standard electrode potential for the cathode?

A. 0.96 V

B. 0.52 V

C. –0.52 V

D. –0.96 V

E. Need to know the cell reaction in order to calculate the answer.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

29. Given that E° for X + e^– → Y is greater than E° for A + 2e^– → B, it is correct to say that, under standard conditions

A. X will oxidize A.

B. Y will oxidize A.

C. Y will reduce A.

D. B will oxidize X.

E. B will reduce X.

Accessibility: Keyboard Navigation

Bloom's: 2. Understand

Difficulty: Medium

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

30. Examine the following half-reactions and select the strongest oxidizing agent among the substances.

[PtCl₄]^2–(aq) + 2e^–Pt(s) + 4Cl^–(aq) E° = 0.755 V

RuO₄(s) + 8H⁺(aq) + 8e^–Ru(s) + 4H₂O(l) E° = 1.038 V

FeO₄^2–(aq) + 8H⁺(aq) + 3e^–Fe³⁺(aq) + 4H₂O(l) E° = 2.07 V

H₄XeO₆(aq) + 2H⁺(aq) + 2e^– XeO₃(aq) + 3H₂O(l) E° = 2.42 V

A. [PtCl₄]^2–(aq)

B. RuO₄(s)

C. HFeO₄^– (aq)

D. H₄XeO₆(aq)

E. Cl^–(aq)

Bloom's: 2. Understand

Difficulty: Medium

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

31. Examine the following half-reactions and select the strongest oxidizing agent among the species listed.

Cr²⁺(aq) + 2e^–Cr(s) E° = –0.913 V

Fe²⁺(aq) + 2e^–Fe(s) E° = –0.447 V

Sr²⁺(aq) + 2e^–Sr(s) E° = –2.89 V

Co²⁺(aq) + 2e^–Co(s) E° = –0.28 V

A. Cr²⁺(aq)

B. Fe(s)

C. Fe²⁺(aq)

D. Sr²⁺(aq)

E. Co²⁺(aq)

Bloom's: 2. Understand

Difficulty: Medium

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

32. Examine the following half-reactions and select the weakest oxidizing agent among the species listed.

AuBr₄(aq) + 3e^–Au(s) + 4Br^–(aq) E° = 0.854 V

Mn²⁺(aq) + 2e^–Mn(s) E° = –1.185 V

K⁺(aq) + e^–K(s) E° = –2.931 V

F₂O(aq) + 2H⁺(aq) + 4e^–2F^–(aq) + H₂O(l) E° = 2.153 V

A. AuBr₄^–(aq)

B. Mn²⁺(aq)

C. K⁺(aq)

D. F₂O(aq)

E. H⁺(aq)

Bloom's: 2. Understand

Difficulty: Medium

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

33. Examine the following half-reactions and select the strongest reducing agent among the species listed.

PbI₂(s) + 2e_–Pb(s) + 2I^–(aq) E° = –0.365 V

Ca²⁺(aq) + 2e^–Ca(s) E° = –2.868 V

Pt²⁺(aq) + 2e^–Pt(s) E° = 1.18 V

Br₂(l) + 2e^–2Br^–(aq) E° = 1.066 V

A. Pb(s)

B. Ca(s)

C. Pt(s)

D. Br^–(aq)

E. Pt²⁺(aq)

Bloom's: 2. Understand

Difficulty: Medium

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

34. Examine the following half-reactions and select the strongest reducing agent among the species listed.

HgO(s) + H2O(l) + 2e^–Hg(l) + 2OH^–(aq) E°= 0.0977 V

Zn(OH)₂(s) + 2e^–Zn(s) + 2OH^–(aq) E° = –1.25 V

Ag₂O(s) + H₂O(l) + 2e^–Ag(s) + 2OH^–(aq) E° = 0.342 V

B(OH)₃(aq) + 7H⁺(aq) + 8e^–BH4^–(aq) + 3H₂O(l) E° = –0.481 V

A. Hg(l)

B. Zn(s)

C. Ag(s)

D. BH₄^–(aq)

E. Zn(OH)₂(s)

Bloom's: 2. Understand

Difficulty: Medium

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

35. Examine the following half-reactions and select the weakest reducing agent among the substances.

Cr(OH)₃(s) + 3e^–Cr(s) + 3OH^–(aq) E° = –1.48 V

SnO₂(s) + 2H₂O(l) + 4e^–Sn(s) + 4OH^–(aq) E° = –0.945 V

MnO₂(s) + 4H⁺(aq) + 2e^–Mn²⁺(aq) + 2H₂O(l) E° = 1.224 V

Hg₂SO₄(s) + 2e^–2Hg(l) + SO₄^2–(aq) E° = 0.613 V

A. Cr(s)

B. Sn(s)

C. Mn²⁺(aq)

D. Hg(l)

E. OH^–(aq)

Bloom's: 2. Understand

Difficulty: Medium

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

36. Calculate E°cell and indicate whether the overall reaction shown is spontaneous or nonspontaneous.

I₂(s) + 2e^–2I^–(aq) E° = 0.53 V

Cr³⁺(aq) + 3e^–Cr(s) E° = –0.74 V

Overall reaction:

2Cr(s) + 3I₂(s) → 2Cr³⁺(aq) + (aq) + 6I^–(aq)

A. E°_cell = –1.27 V, spontaneous

B. E° _cell = –1.27 V, nonspontaneous

C. E° _cell = 1.27 V, spontaneous

D. E° _cell = 1.27 V, nonspontaneous

E. E° _cell = 1.54 V, spontaneous

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

37. Calculate E°cell and indicate whether the overall reaction shown is spontaneous or nonspontaneous.

Co³⁺(aq) + e^–Co²⁺(aq) E° = 1.82 V

MnO₄^–(aq) + 2H₂O(l) + 3e^– MnO₂(s) + 4OH^–(aq) E° = 0.59 V

Overall reaction:

MnO₄^–(aq) + 2H₂O(l) + 3Co²⁺(aq) → MnO₂(s) + 3Co³⁺(aq) + 4OH^–(aq)

A. E° _cell = –1.23 V, spontaneous

B. E° _cell = –1.23 V, nonspontaneous

C. E° _cell = 1.23 V, spontaneous

D. E° _cell = 1.23 V, nonspontaneous

E. E° _cell = –0.05 V, nonspontaneous

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

38. Calculate E° _cell and indicate whether the overall reaction shown is spontaneous or nonspontaneous.

O₂(g) + 4H⁺(aq) + 4e^–2H₂O(l) E° = 1.229 V

Al³⁺(aq) + 3e^–Al(s) E° = –1.662 V

Overall reaction:

4Al(s) + 3O₂(g) + 12H⁺(aq) → 4Al³⁺(aq) + 6H₂O(l)

A. E° _cell = –2.891 V, nonspontaneous

B. E° _cell = –2.891 V, spontaneous

C. E° _cell = 2.891 V, nonspontaneous

D. E° _cell = 2.891 V, spontaneous

E. None of these choices are correct.

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

39. Calculate E° _cell and indicate whether the overall reaction shown is spontaneous or nonspontaneous.

H₂O₂(aq) + 2H⁺(aq) + 2e^– 2H₂O(l) E° = 1.77 V

Fe³⁺ (aq) + e^– Fe²⁺(aq) E° = 0.77 V

Overall reaction:

2Fe³⁺(aq) + 2H₂O(l) → H₂O₂(aq) + 2H⁺(aq) + 2Fe²⁺(aq)

A. E° _cell = –1.00 V, nonspontaneous

B. E° _cell = –1.00 V, spontaneous

C. E° _cell = 1.00 V, nonspontaneous

D. E° _cell = 1.00 V, spontaneous

E. E° _cell = –0.23 V, nonspontaneous

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

40. When metal A is placed in a solution of metal ions B²⁺, a reaction occurs between A and B²⁺, and metal ions A²⁺ appear in the solution. When metal B is placed in acid solution, gas bubbles form on its surface. When metal A is placed in a solution of metal ions C²⁺, no reaction occurs.

Which of the following reactions would not occur spontaneously?

A. C(s) + 2^H+(aq) → H₂(g) + C+(aq)

B. C(s) + A²⁺(aq) → A(s) + C²⁺(aq)

C. B(s) + C²⁺(aq) → C(s) + B²⁺(aq)

D. A(s) + 2^H+(aq) → H₂(g) + A²⁺(aq)

E. B(s) + 2H⁺(aq) → H₂(g) + B²⁺(aq)

Accessibility: Keyboard Navigation

Bloom's: 2. Understand

Difficulty: Hard

Gradable: automatic

Subtopic: Standard Reduction (Cell) Potentials

Topic: Electrochemistry

41. Which of the following conditions is most likely to apply to a fully-charged secondary cell?

A. E _cell l = E° _cell

B. E° _cell = 0

C. = 1

D. < K

E. = K

Bloom's: 1. Remember

Difficulty: Medium

Gradable: automatic

Subtopic: Batteries

Topic: Electrochemistry

42. A battery is considered “dead” when

A. < 1.

B. = 1.

C. > 1.

D. = K.

E. /K = 0.

Bloom's: 1. Remember

Difficulty: Easy

Gradable: automatic

Subtopic: Batteries

Topic: Electrochemistry

43. Calculate the potential of a voltaic cell (E° _cell) if it is required to do 5.43 × 10^–3 kJ of work when a charge of 2.50 C is transferred.

A. 2.17 × 10³ V

B. 2.17 × 10^–3 V

C. 2.17 V

D. 13.6 V

E. 1.36 × 10^–2 V

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Batteries

Topic: Electrochemistry

44. What is the value of the equilibrium constant for the cell reaction below at 25°C? E° _cell = 0.30 V

Sn²⁺(aq) + Fe(s) Sn(s) + Fe²⁺(aq)

A. 1.2 × 10⁵

B. 1.4 × 10¹⁰

C. 8.6 × 10^–6

D. 7.1 × 10^–11

E. 2.3 × 10²³

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrical Work and Free Energy

Topic: Electrochemistry

45. What is the value of the equilibrium constant for the cell reaction below at 25°C? E° _cell = 0.61 V

2Cr(s) + 3Pb²⁺(aq) 3Pb(s) + 2Cr³⁺(aq)

A. 4.1 × 10²⁰

B. 8.2 × 10³⁰

C. 3.3 × 10⁵¹

D. 7.4 × 10⁶¹

E. > 9.9 × 10⁹⁹

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrical Work and Free Energy

Topic: Electrochemistry

46. The following half-reactions occur in the mercury battery used in calculators. If E° _cell = 1.357 V, calculate the equilibrium constant for the cell reaction at 25°C. (Assume the stoichiometric coefficients in the cell reaction are all equal to 1.)

HgO(s) + H₂O(l) + 2e^–Hg(l) + 2OH^–(aq)

ZnO(s) + H₂O(l) + 2e^–Zn(s) + 2OH^–(aq)

A. 9.4 × 10²²

B. 7.5 × 10⁴⁵

C. 6.4 × 10⁶³

D. 7.8 × 10⁹¹

E. > 9.9 × 10⁹⁹

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrical Work and Free Energy

Topic: Electrochemistry

47. Consider the nonaqueous cell reaction

2Na(l) + FeCl₂(s) 2NaCl(s) + Fe(s)

for which E° _cell = 2.35 V at 200°C. ΔG° at this temperature is

A. 453 kJ.

B. –453 kJ.

C. 907 kJ.

D. –907 kJ.

E. None of these choices are correct.

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrical Work and Free Energy

Topic: Electrochemistry

48. Consider the reaction in the lead-acid cell

Pb(s) + PbO₂(s) + 2H₂SO₄(aq) → 2PbSO₄(aq) + 2H₂O(l)

for which E° _cell = 2.04 V at 298 K. ΔG° for this reaction is

A. –3.94 × 10⁵ kJ.

B. –3.94 × 10² kJ.

C. –1.97 × 10⁵ kJ.

D. –7.87 × 10² kJ.

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrical Work and Free Energy

Topic: Electrochemistry

49. The value of E° _cell for the reaction

2Cr³⁺(aq) + 6Hg(l) → 2Cr(s) + 3Hg₂²⁺(aq)

is 1.59 V. Calculate ΔG° for the reaction.

A. –921 kJ

B. –767 kJ

C. –460 kJ

D. –307 kJ

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrical Work and Free Energy

Topic: Electrochemistry

50. Calculate ΔG° for the reaction of iron(II) ions with one mole of permanganate ions.

MnO₄–(aq) + 8H+(aq) + 5e–Mn₂+(aq) + 4H₂O(l) E° = 1.51 V

Fe³⁺(aq) + e^–Fe²⁺(aq) E°= 0.77 V

A. –71.4 kJ

B. –286 kJ

C. –357 kJ

D. –428 kJ

E. None of these choices are correct.

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrical Work and Free Energy

Topic: Electrochemistry

51. Calculate ΔG° for the oxidation of 3 moles of copper by nitric acid.

Cu²⁺(aq) + 2e^–Cu(s) E° = 0.34 V

NO₃^–(aq) + 4H⁺(aq) + 3e^–NO(g) + 2H²O(l) E° = 0.957 V

A. –120 kJ

B. –180 kJ

C. –240 kJ

D. –300 kJ

E. –360 kJ

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrical Work and Free Energy

Topic: Electrochemistry

52. The value of the equilibrium constant for the reaction of nickel(II) ions with cadmium metal is 1.17 × 10⁵. Calculate ΔG° for the reaction at 25°C.

A. –12.6 kJ

B. –28.9 kJ

C. 12.6 kJ

D. 28.9 kJ

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrical Work and Free Energy

Topic: Electrochemistry

53. Calculate E° _cell for the reaction of nickel(II) ions with cadmium metal at 25°C. K = 1.17 × 10⁵

Ni²⁺(aq) + Cd(s) → Cd²⁺(aq) + Ni(s)

A. 0.075 V

B. 0.10 V

C. 0.12 V

D. 0.15 V

E. 0.30 V

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrical Work and Free Energy

Topic: Electrochemistry

54. Consider the reaction of iodine with manganese dioxide

3I₂(s) + 2MnO₂(s) + 8OH^–(aq) 6I^–(aq) + 2MnO₄(aq) + 4H₂O(l)

The equilibrium constant for the overall reaction is 8.30 × 10^–7. Calculate ΔG° for the reaction at 25°C.

A. –15.1 kJ

B. –34.7 kJ

C. 15.1 kJ

D. 34.7 kJ

E. None of these choices are correct.

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrical Work and Free Energy

Topic: Electrochemistry

55. Consider the reaction of iodine with manganese dioxide

3I₂(s) + 2MnO₂(s) + 8OH^–(aq) 6I^–(aq) + 2MnO₄(aq) + 4H₂O(l)

The equilibrium constant for the overall reaction is 8.30 × 10^–7. Calculate E° _cell for the reaction at 25°C.

A. –0.36 V

B. –0.18 V

C. –0.12 V

D. –0.060 V

E. None of these choices are correct.

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrical Work and Free Energy

Topic: Electrochemistry

56. A voltaic cell consists of a Mn/Mn²⁺ electrode (E° = –1.18 V) and a Fe/Fe²⁺ electrode (E° = –0.44 V). Calculate [Fe²⁺] if [Mn²⁺] = 0.050 M and E _cell = 0.78 V at 25°C.

A. 0.040 M

B. 0.24 M

C. 1.1 M

D. 1.8 M

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Hard

Gradable: automatic

Subtopic: Concentration and Cell Potential (Nernst Equation)

Topic: Electrochemistry

57. A voltaic cell consists of an Au/Au³⁺ electrode (E° = 1.50 V) and a Cu/Cu²⁺ electrode (E° = 0.34 V). Calculate [Au³⁺] if [Cu²⁺] = 1.20 M and E_cell = 1.13 V at 25°C.

A. 0.001 M

B. 0.002 M

C. 0.01 M

D. 0.02 M

E. 0.04 M

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Hard

Gradable: automatic

Subtopic: Concentration and Cell Potential (Nernst Equation)

Topic: Electrochemistry

58. A voltaic cell consists of a Hg/Hg2²⁺ electrode (E° = 0.85 V) and a Sn/Sn²⁺ electrode (E° = –0.14 V). Calculate [Sn²⁺] if [Hg₂²⁺] = 0.24 M and E_cell = 1.04 V at 25°C.

A. 0.0001 M

B. 0.0007 M

C. 0.005 M

D. 0.03 M

E. 0.05 M

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Hard

Gradable: automatic

Subtopic: Concentration and Cell Potential (Nernst Equation)

Topic: Electrochemistry

59. A voltaic cell consists of a Cd/Cd²⁺ electrode (E° = –0.40 V) and a Fe/Fe²⁺ electrode (E° = –0.44 V). If E_cell = 0 and the temperature is 25°C, what is the ratio [Fe²⁺]/[Cd²⁺]?

A. 2 × 10¹

B. 1 × 10¹

C. 1

D. 1 × 10^–1

E. 5 × 10^–2

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Hard

Gradable: automatic

Subtopic: Concentration and Cell Potential (Nernst Equation)

Topic: Electrochemistry

60. A voltaic cell consists of a Ag/Ag⁺ electrode (E° = 0.80 V) and a Fe²⁺/Fe³⁺ electrode (E° = 0.77 V) with the following initial molar concentrations: [Fe²⁺] = 0.30 M; [Fe³⁺] = 0.10 M; [Ag⁺] = 0.30 M. What is the equilibrium concentration of Fe³⁺? (Assume the anode and cathode solutions are of equal volume, and a temperature of 25°C.)

A. 0.030 M

B. 0.043 M

C. 0.085 M

D. 0.11 M

E. 0.17 M

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Hard

Gradable: automatic

Subtopic: Concentration and Cell Potential (Nernst Equation)

Topic: Electrochemistry

61. A concentration cell consists of two Zn/Zn²⁺ electrodes. The electrolyte in compartment A is 0.10 M Zn(NO₃)₂ and in compartment B is 0.60 M Zn(NO₃)₂. What is the voltage of the cell at 25°C?

A. 0.010 V

B. 0.020 V

C. 0.023 V

D. 0.046 V

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Concentration and Cell Potential (Nernst Equation)

Topic: Electrochemistry

62. A concentration cell consists of two Al/Al³⁺electrodes. The electrolyte in compartment A is 0.050 M Al(NO₃)₃ and in compartment B is 1.25 M Al(NO₃)₃. What is the voltage of the cell at 25°C?

A. 0.083 V

B. 0.062 V

C. 0.041 V

D. 0.028 V

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Concentration and Cell Potential (Nernst Equation)

Topic: Electrochemistry

63. Which one of the following statements relating to the glass electrode is correct?

A. The glass electrode detects hydrogen gas.

B. The glass of a glass electrode serves to conduct electrons.

C. When pH is measured, only a single electrode, the glass electrode, need be used.

D. The potential of the glass electrode varies linearly with the pH of the solution.

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Medium

Gradable: automatic

Subtopic: Concentration and Cell Potential (Nernst Equation)

Topic: Electrochemistry

64. A battery that cannot be recharged is a

A. fuel cell.

B. primary battery.

C. secondary battery.

D. simple battery.

E. flow battery.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Easy

Gradable: automatic

Subtopic: Batteries

Topic: Electrochemistry

65. Which, if any, of the following metals would be capable of acting as a sacrificial anode when used with iron pipe? E°_Fe = –0.44 V; all E° values refer to the M²⁺/M half-cell reactions.

A. copper, Cu, E° = 0.15 V

B. cobalt, Co, E° = –0.28 V

C. chromium, Cr, E° = –0.74 V

D. tin, Sn, E° = –0.14 V

E. None of these metals would be capable of acting as a sacrificial anode with iron.

Accessibility: Keyboard Navigation

Bloom's: 2. Understand

Difficulty: Easy

Gradable: automatic

Subtopic: Corrosion

Topic: Electrochemistry

66. Which, if any, of the following metals would not be capable of acting as a sacrificial anode when used with iron E°_Fe = –0.44 V; all E° values refer to the M²⁺/M half-cell reactions.

A. manganese, Mn, E° = –1.18 V

B. cadmium, Cd, E° = –0.40 V

C. magnesium, Mg, E° = –2.37 V

D. zinc, Zn, E° = –0.76 V

E. All of these metals are capable of acting as sacrificial anodes with iron.

Accessibility: Keyboard Navigation

Bloom's: 2. Understand

Difficulty: Easy

Gradable: automatic

Subtopic: Corrosion

Topic: Electrochemistry

67. What product forms at the cathode during the electrolysis of molten lithium iodide?

A. Li⁺(l)

B. Li(l)

C. I^–(l)

D. I₂(g)

E. I₃^–(l)

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

68. What product forms at the anode during the electrolysis of molten NaBr?

A. Na⁺(l)

B. Na(l)

C. Br^–(l)

D. Br3^–(l)

E. Br₂(g)

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

69. Which of the following elements could be prepared by electrolysis of the aqueous solution shown?

A. sodium from Na₃PO₄(aq)

B. sulfur from K₂SO₄(aq)

C. oxygen from H₂SO₄(aq)

D. potassium from KCl(aq)

E. nitrogen from AgNO₃(aq)

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Hard

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

70. Which of the following elements can be isolated by electrolysis of the aqueous salt shown?

A. phosphorus from K₃PO₄(aq)

B. sodium from NaBr(aq)

C. aluminum from AlCl₃(aq)

D. fluorine from KF(aq)

E. iodine from NaI(aq)

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Hard

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

71. In the electrolysis of aqueous potassium nitrate using inert electrodes, which one of the following species is oxidized?

A. potassium ion

B. nitrate ion

C. water

D. oxygen

E. hydronium ion

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

72. In the electrolysis of aqueous sodium sulfate at electrodes of platinum, predict the products of the cell reaction.

A. sodium and sulfur

B. hydrogen and sulfur

C. oxygen and sulfur

D. oxygen and sulfuric acid

E. hydrogen and oxygen

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

73. Predict the products of the cell reaction when a molten salt mixture of sodium bromide and calcium fluoride is electrolyzed (spectator ions are not considered to be products).

A. calcium and bromine

B. sodium and fluorine

C. calcium bromide

D. calcium and fluorine

E. sodium and bromine

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

74. What mass of silver will be formed when 15.0 A are passed through molten AgCl for 25.0 minutes?

A. 0.419 g

B. 6.29 g

C. 12.6 g

D. 25.2 g

E. 33.4 g

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

75. What mass of copper will be deposited when 18.2 A are passed through a CuSO₄ solution for 45.0 minutes?

A. 16.2 g

B. 33.4 g

C. 40.6 g

D. 81.3 g

E. 163 g

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

76. A solution is prepared by dissolving 32.0 g of NiSO₄ in water. What current would be needed to deposit all of the nickel in 5.0 hours?

A. 1.1 A

B. 2.2 A

C. 3.3 A

D. 4.4 A

E. 5.5 A

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

77. How many grams of oxygen gas will be produced in the electrolysis of water, for every gram of hydrogen gas formed?

Reaction: 2H₂O(l) → 2H₂(g) + O₂(g)

A. 31.7 g

B. 15.9 g

C. 7.94 g

D. 3.97 g

E. 1.98 g

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

78. Two cells are connected in series, so that the same current flows through two electrodes where the following half-reactions occur

Cu²⁺(aq) + 2e^– → Cu(s) and Ag⁺(aq) + e_– → Ag(s)

For every 1.00 g of copper produced in the first process, how many grams of silver will be

produced in the second one?

A. 0.294 g

B. 0.588 g

C. 0.850 g

D. 1.70 g

E. 3.40 g

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

79. A current of 250. A flows for 24.0 hours at an anode where the reaction occurring is Mn²⁺(aq) + 2H₂O(l) → MnO₂(s) + 4H⁺(aq) + 2e^–

What mass of MnO2 is deposited at this anode?

A. 19.5 kg

B. 12.9 kg

C. 4.87 kg

D. 2.43 kg

E. None of these choices are correct.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

80. Chromium metal is electroplated from acidic aqueous solutions containing the dichromate ion, Cr₂O7^2–. What is the minimum time needed to plate out 10.0 g of chromium metal from such a solution, if the current is 50.0 A?

A. 6.2 minutes

B. 12.4 minutes

C. 18.6 minutes

D. 24.7 minutes

E. 37.1 minutes

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

81. Electrolytic cells utilize electrical energy to drive nonspontaneous redox reactions.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Easy

Gradable: automatic

Subtopic: Electrolytic Cells

Topic: Electrochemistry

82. For the reaction occurring in a voltaic (galvanic) cell, ΔG > 0.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Easy

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

83. Oxidation occurs at the cathode of a galvanic cell, but at the anode of an electrolytic cell.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

84. Electrons are produced at the cathode of a voltaic cell.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

85. If the electrodes of a voltaic cell are connected with an external wire, electrons will flow in this wire from the cathode to the anode.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

86. In the electrolyte of an electrochemical cell, current is carried by anions moving toward the anode and cations moving in the opposite direction.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

87. In the electrolyte of an electrochemical cell, current is carried by electrons moving from the anode to the cathode.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Easy

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

88. A salt bridge provides a path for electrons to move between the anode and cathode compartments of a voltaic cell.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Easy

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

89. In the shorthand notation for cells, a double vertical line is used to separate the reduced and oxidized forms of a redox couple.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Easy

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

90. In the shorthand notation for cells, a single vertical line represents a salt bridge.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Easy

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

91. A secondary cell (battery) can operate either as a galvanic or an electrolytic cell.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Medium

Gradable: automatic

Subtopic: Batteries

Topic: Electrochemistry

92. The lead-acid battery is an example of a secondary battery.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Easy

Gradable: automatic

Subtopic: Batteries

Topic: Electrochemistry

93. A primary battery is one that can be recharged.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Easy

Gradable: automatic

Subtopic: Batteries

Topic: Electrochemistry

94. In a fuel cell, an external source of electrical power is used to drive a nonspontaneous reaction in which a fuel is produced.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Medium

Gradable: automatic

Subtopic: Batteries

Topic: Electrochemistry

95. In the absence of oxygen, iron will rust as long as moisture is present.

Accessibility: Keyboard Navigation

Bloom's: 2. Understand

Difficulty: Medium

Gradable: automatic

Subtopic: Corrosion

Topic: Electrochemistry

96. A buried iron pipe can be protected against corrosion by connecting it to a rod of magnesium.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Medium

Gradable: automatic

Subtopic: Corrosion

Topic: Electrochemistry

97.A buried iron pipe can be protected against corrosion by connecting it to a rod of copper.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Medium

Gradable: automatic

Subtopic: Corrosion

Topic: Electrochemistry

98. A voltaic cell is based on the following two half-reactions:

Ni⁺²(aq) + 2e⁻ → Ni(s) E° = −0.25 V

Cr⁺³(aq) + 3e^– → Cr(s) E° = –0.74 V

Sketch the cell and then select the correct statement about it.

A. Cr serves as the cathode.

B. The direction of electron flow through the external wire is from the Ni to the Cr electrode.

C. Anions in solution will migrate toward the Ni+2/Ni electrode.

D. The net cell reaction is 3Ni⁺²(aq) + 2Cr(s) → 3Ni(s) + 2Cr⁺³(aq)

E. = 0.99 V

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Voltaic (Galvanic) Cells

Topic: Electrochemistry

99. Which of the following types of electrochemical cell is most likely to find use in the future as a power source for electric vehicles?

A. fuel cell

B. nickel-metal hydride cell

C. dry cell

D. alkaline battery

E. lithium-ion battery

Accessibility: Keyboard Navigation

Bloom's: 2. Understand

Difficulty: Easy

Gradable: automatic

Subtopic: Batteries

Topic: Electrochemistry

100. Select the incorrect statement relating to the corrosion of iron in air.

A. Fe²⁺ is formed in the anodic region.

B. O₂ is oxidized in the cathodic region.

C. Electrons travel through the iron metal between the anodic and cathodic regions.

D. Moisture provides a pathway for ions to migrate.

E. Rust is a hydrated form of iron(III) oxide.

Accessibility: Keyboard Navigation

Bloom's: 1. Remember

Difficulty: Easy

Gradable: automatic

Subtopic: Oxidation-Reduction (REDOX) Reactions (Definition and Balancing)

Topic: Electrochemistry

101. If the equilibrium constant K_c is greater than 1 for a given reaction, predict the signs of ΔG° and E° at the same temperature.

A. ΔG° > 0; E° > 0

B. ΔG° < 0; E° < 0

C. ΔG° > 0; E° < 0

D. ΔG° < 0; E° > 0

E. Cannot predict - it depends on the temperature.

Accessibility: Keyboard Navigation

Bloom's: 3. Apply

Difficulty: Medium

Gradable: automatic

Subtopic: Concentration and Cell Potential (Nernst Equation)

Topic: Electrochemistry

Category # of Questions

Accessibility: Keyboard Navigation 77

Bloom's: 1. Remember 25

Bloom's: 2. Understand 18

Bloom's: 3. Apply 58

Difficulty: Easy 21

Difficulty: Hard 8

Difficulty: Medium 68

Difficulty: Easy 2

Difficulty: Medium 2

Gradable: automatic 101

Subtopic: Batteries 9

Subtopic: Concentration and Cell Potential (Nernst Equation) 9

Subtopic: Corrosion 5

Subtopic: Electrical Work and Free Energy 12

Subtopic: Electrolytic Cells 15

Subtopic: Oxidation-Reduction (REDOX) Reactions (Definition and Balancing) 11

Subtopic: Standard Reduction (Cell) Potentials 18

Subtopic: Voltaic (Galvanic) Cells 22

Topic: Electrochemistry 4

Topic: Electrochemistry 97