Question 1

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?

Accepted Answer

A)  1.1 A
B)  2.2 A
C)  3.3 A
D)  4.4 A
E)  5.5 AF) A) and D)
G) A) and C)

Question 2

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.

Accepted Answer

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.F) B) and D)
G) A) and E)

Question 3

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

Accepted Answer

A)  Fe 2+ is formed in the anodic region.
B)  O 2 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.F) A) and C)
G) A) and D)

Question 4

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

Accepted Answer

A) True 
 B)False

Question 5

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

Accepted Answer

A)  AuBr 4−( aq) 
B)  Mn 2+( aq) 
C)  K +( aq) 
D)  F 2O( aq) 
E)  H +( aq) F) A) and B)
G) D) and E)

Question 6

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

Accepted Answer

A) True 
 B)False

Question 7

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

Accepted Answer

A)  2 × 10 1
B)  1 × 10 1
C)  1
D)  1 × 10 −1
E)  5 × 10 −2F) A) and D)
G) C) and D)

Question 8

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

Accepted Answer

A) True 
 B)False

Question 9

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

Accepted Answer

A)  Li +( l) 
B)  Li( l) 
C)  I −( l) 
D)  I 2( g) 
E)  I 3 −( l) F) A) and C)
G) A) and B)

Question 10

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- ⇄ VO(aq)  + H2O(l)  E° = 0.991 V

Accepted Answer

A)  -0.398 V
B)  -2.380 V
C)  0.398 V
D)  2.380 V
E)  None of these choices are correct.F) A) and B)
G) A) and C)

Question 11

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

Accepted Answer

A)  copper metal is a product of the cell reaction.
B)  hydrogen gas (H 2) is a product of the cell reaction.
C)  Cu is the anode.
D)  Pt is the cathode.
E)  Cu 2+ is the reducing agent.F) A) and B)
G) B) and E)

Question 12

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

Accepted Answer

A) True 
 B)False

Question 13

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

Accepted Answer

A) True 
 B)False

Question 14

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?

Accepted Answer

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.F) C) and D)
G) C) and E)

Question 15

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?

Accepted Answer

A)  0.010 V
B)  0.020 V
C)  0.023 V
D)  0.046 V
E)  None of these choices are correct.F) B) and E)
G) B) and C)

Question 16

A primary battery is one that can be recharged.

Accepted Answer

A) True 
 B)False

Question 17

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) .

Accepted Answer

A)  Calcium and Bromine
B)  Sodium and Fluorine
C)  Calcium bromide
D)  Calcium and Fluorine
E)  Sodium and BromineF) A) and B)
G) A) and C)

Question 18

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)

Accepted Answer

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, nonspontaneousF) A) and E)
G) A) and D)

Question 19

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

Accepted Answer

A) True 
 B)False

Question 20

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

Accepted Answer

A)  Na +( l) 
B)  Na( l) 
C)  Br −( l) 
D)  Br 3 −( l) 
E)  Br 2( g) F) B) and C)
G) B) and D)

Exam 21: Electrochemistry: Chemical Change and Electrical Work

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

Correct Answer
verified

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

Correct Answer
verified

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⁺]?

Correct Answer
verified

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)

Correct Answer
verified

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

Correct Answer
verified

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

Correct Answer
verified

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

Correct Answer
verified

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

Correct Answer
verified

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) .

Correct Answer
verified

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

Correct Answer
verified

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.

Correct Answer
verified

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

Correct Answer
verified

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?

Correct Answer
verified

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?

Correct Answer
verified

A primary battery is one that can be recharged.

Correct Answer
verified

Correct Answer
verified

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^- ⇄ VO(aq) + H₂O(l) E° = 0.991 V

Correct Answer
verified

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

Correct Answer
verified

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

Correct Answer
verified

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

Correct Answer
verified

Exam 21: Electrochemistry: Chemical Change and Electrical Work

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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)

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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) .

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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.

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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?

Correct AnswerverifiedShow Answer

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?

Correct AnswerverifiedShow Answer

A primary battery is one that can be recharged.

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

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- ⇄ VO(aq) + H2O(l) E° = 0.991 V

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

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⁺]?

Correct Answer
verified

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)

Correct Answer
verified

Correct Answer
verified

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

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

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.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

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?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

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^- ⇄ VO(aq) + H₂O(l) E° = 0.991 V

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

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

Correct Answer
verified