Question 1

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?

Accepted Answer

A) Cu(s) $\to$ Cu2+(aq)+ 2e- 
B) Cu2+(aq)+ 2e- $\to$ Cu(s) 
C) Ag(s) $\to$ Ag+(aq)+ e- 
D) Ag+(aq)+ e-  $\to$ Ag(s) 
E) Cu(s)+ 2Ag+(aq) $\to$ Cu2+(aq)+ 2Ag(s)

Question 2

A concentration cell is based on the aqueous reaction Cu²⁺(1.00 M) $\to$ Cu²⁺(0.0100 M) The cell consists of copper electrodes dipping into solutions of Cu²⁺ ions.The anions present are sulfate ions.Write the shorthand cell notation for this cell.

Accepted Answer

The answer of A concentration cell is based on the...

Question 3

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

Accepted Answer

A) True 
 B)False

Question 4

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

Accepted Answer

A) True 
 B)False

Question 5

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

Accepted Answer

A) Hg(l) 
B) Zn(s) 
C) Ag(s) 
D) BH4-(aq) 
E) Zn(OH)2(s)

Question 6

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) $\to$ 2Cr3+(aq)+ (aq)+ 6I-(aq)

Accepted Answer

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

Question 7

A galvanic cell is constructed using the two hypothetical half-reactions a.Write down the balanced equation representing the cell reaction. b.Calculate the standard potential of this cell,E°_cell. c.Calculate $\Delta$G° for the cell reaction.

Accepted Answer

The answer of A galvanic cell is constructed using the...

Question 8

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

Accepted Answer

A) zinc 
B) graphite 
C) copper 
D) iron 
E) sodium

Question 9

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 is correct.

Question 10

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 A

Question 11

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)

Accepted Answer

A) 1.2 $\times$ 105 
B) 1.4 $\times$ 1010 
C) 8.6 $\times$ 10-6 
D) 7.1 $\times$ 10-11 
E) 2.3 $\times$ 1023

Question 12

The value of the equilibrium constant for the reaction of nickel(II)ions with cadmium metal is 1.17 $\times$ 105.Calculate $\Delta$G° for the reaction at 25°C.

Accepted Answer

A) -12.6 kJ 
B) -28.9 kJ 
C) 12.6 kJ 
D) 28.9 kJ 
E) None of these choices is correct.

Question 13

A concentration cell is based on the aqueous reaction Cu²⁺(1.00 M) $\to$ Cu²⁺(0.0100 M) The cell consists of copper electrodes dipping into solutions of Cu²⁺ ions.The anions present are sulfate ions.Draw a neat diagram to represent this cell,showing and labeling all necessary components including: anode,cathode,electron flow,cation flow and anion flow.

Accepted Answer

The answer of A concentration cell is based on the...

Question 14

The value of E°cell for the reaction
2Cr3+(aq)+ 6Hg(l) $\to$ 2Cr(s)+ 3Hg22+(aq)
Is 1.59 V.Calculate $\Delta$G° for the reaction.

Accepted Answer

A) -921 kJ 
B) -767 kJ 
C) -460 kJ 
D) -307 kJ 
E) None of these choices is correct.

Question 15

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. )

Accepted Answer

A) 0.030 M 
B) 0.043 M 
C) 0.085 M 
D) 0.11 M 
E) 0.17 M

Question 16

Electrolytic cells utilize electrical energy to drive non-spontaneous redox reactions.

Accepted Answer

A) True 
 B)False

Question 17

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?

Accepted Answer

A) 0.083 V 
B) 0.062 V 
C) 0.041V 
D) 0.028 V 
E) None of these choices is correct.

Question 18

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 19

A concentration cell is based on the aqueous reaction Cu²⁺(1.00 M) $\to$ Cu²⁺(0.0100 M) Calculate the potential of this cell if it operates at 25.0°C.

Accepted Answer

The answer of A concentration cell is based on the...

Question 20

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)

Accepted Answer

A) 9.4 $\times$ 1022 
B) 7.5 $\times$ 1045 
C) 6.4 $\times$ 1063 
D) 7.8 $\times$ 1091 
E) > 9.9 $\times$ 1099

Exam 21: Electrochemistry: Chemical Change and Electrical Work

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 concentration cell is based on the aqueous reaction Cu²⁺(1.00 M) $\to$ Cu²⁺(0.0100 M) The cell consists of copper electrodes dipping into solutions of Cu²⁺ ions.The anions present are sulfate ions.Write the shorthand cell notation for this cell.

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

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

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

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 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?

The value of the equilibrium constant for the reaction of nickel(II) ions with cadmium metal is 1.17 $\times$ 10⁵.Calculate $\Delta$ G° for the reaction at 25°C.

The value of E°_cell for the reaction 2Cr³⁺(aq) + 6Hg(l) $\to$ 2Cr(s) + 3Hg₂²⁺(aq) Is 1.59 V.Calculate $\Delta$ G° for the reaction.

Electrolytic cells utilize electrical energy to drive non-spontaneous redox reactions.

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?

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

A concentration cell is based on the aqueous reaction Cu²⁺(1.00 M) $\to$ Cu²⁺(0.0100 M) Calculate the potential of this cell if it operates at 25.0°C.

Exam 21: Electrochemistry: Chemical Change and Electrical Work

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 concentration cell is based on the aqueous reaction Cu2+(1.00 M) →\to→ Cu2+(0.0100 M) The cell consists of copper electrodes dipping into solutions of Cu2+ ions.The anions present are sulfate ions.Write the shorthand cell notation for this cell.

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

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

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) →\to→ 2Cr3+(aq) + (aq) + 6I-(aq)

A galvanic cell is constructed using the two hypothetical half-reactions a.Write down the balanced equation representing the cell reaction. b.Calculate the standard potential of this cell,E°cell. c.Calculate Δ\DeltaΔ G° for the cell reaction.

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

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 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?

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)

The value of the equilibrium constant for the reaction of nickel(II) ions with cadmium metal is 1.17 ×\times× 105.Calculate Δ\DeltaΔ G° for the reaction at 25°C.

The value of E°cell for the reaction 2Cr3+(aq) + 6Hg(l) →\to→ 2Cr(s) + 3Hg22+(aq) Is 1.59 V.Calculate Δ\DeltaΔ G° for the reaction.

Electrolytic cells utilize electrical energy to drive non-spontaneous redox reactions.

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?

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

A concentration cell is based on the aqueous reaction Cu2+(1.00 M) →\to→ Cu2+(0.0100 M) Calculate the potential of this cell if it operates at 25.0°C.

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 concentration cell is based on the aqueous reaction Cu²⁺(1.00 M) $\to$ Cu²⁺(0.0100 M) The cell consists of copper electrodes dipping into solutions of Cu²⁺ ions.The anions present are sulfate ions.Write the shorthand cell notation for this cell.

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 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?

The value of the equilibrium constant for the reaction of nickel(II) ions with cadmium metal is 1.17 $\times$ 10⁵.Calculate $\Delta$ G° for the reaction at 25°C.

The value of E°_cell for the reaction 2Cr³⁺(aq) + 6Hg(l) $\to$ 2Cr(s) + 3Hg₂²⁺(aq) Is 1.59 V.Calculate $\Delta$ G° for the reaction.

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 concentration cell is based on the aqueous reaction Cu²⁺(1.00 M) $\to$ Cu²⁺(0.0100 M) Calculate the potential of this cell if it operates at 25.0°C.