Question 1

A battery is considered "dead" when

Accepted Answer

A)     1. 
D)    = K. 
E)    /K = 0. 
A)     1. 
D)    = K. 
E)    /K = 0.

Question 2

Consider the reaction CuO(s) + H2(g) → Cu(s) + H2O(l)
In this reaction, which substances are the oxidant and reductant, respectively?

Accepted Answer

A)  CuO and H2 
B)  H2 and CuO 
C)  CuO and Cu 
D)  H2O and H2 
E)  None of these choices are correct. 
A)  CuO and H2 
B)  H2 and CuO 
C)  CuO and Cu 
D)  H2O and H2 
E)  None of these choices are correct.

Question 3

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 
A)  1.1 A 
B)  2.2 A 
C)  3.3 A 
D)  4.4 A 
E)  5.5 A

Question 4

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

Accepted Answer

A) True 
 B)False

Question 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)

Accepted Answer

A)  1 
B)  2 
C)  4 
D)  10 
E)  None of these choices are correct. 
A)  1 
B)  2 
C)  4 
D)  10 
E)  None of these choices are correct.

Question 6

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.

Accepted Answer

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

Question 7

Electrolytic cells utilize electrical energy to drive nonspontaneous redox reactions.

Accepted Answer

A) True 
 B)False

Question 8

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

Accepted Answer

A)  -120 kJ 
B)  -180 kJ 
C)  -240 kJ 
D)  -300 kJ 
E)  -360 kJ 
A)  -120 kJ 
B)  -180 kJ 
C)  -240 kJ 
D)  -300 kJ 
E)  -360 kJ

Question 9

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)  AuBr4-(aq) 
B)  Mn2+(aq) 
C)  K+(aq) 
D)  F2O(aq) 
E)  H+(aq) 
A)  AuBr4-(aq) 
B)  Mn2+(aq) 
C)  K+(aq) 
D)  F2O(aq) 
E)  H+(aq)

Question 10

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

Question 11

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)

Accepted Answer

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 
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

Question 12

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)

Accepted Answer

A)  0.075 V 
B)  0.10 V 
C)  0.12 V 
D)  0.15 V 
E)  0.30 V 
A)  0.075 V 
B)  0.10 V 
C)  0.12 V 
D)  0.15 V 
E)  0.30 V

Question 13

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)62-(aq) + Bi(s) (basic solution)

Accepted Answer

A)  1. 
B)  2. 
C)  3. 
D)  6. 
E)  None of these choices are correct. 
A)  1. 
B)  2. 
C)  3. 
D)  6. 
E)  None of these choices are correct.

Question 14

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

Accepted Answer

A)  0.47 V 
B)  0.21 V 
C)  -0.21 V 
D)  -0.47 V 
E)  0.42 V 
A)  0.47 V 
B)  0.21 V 
C)  -0.21 V 
D)  -0.47 V 
E)  0.42 V

Question 15

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)

Accepted Answer

A)  4.1 × 1020 
B)  8.2 × 1030 
C)  3.3 × 1051 
D)  7.4 × 1061 
E)  > 9.9 × 1099 
A)  4.1 × 1020 
B)  8.2 × 1030 
C)  3.3 × 1051 
D)  7.4 × 1061 
E)  > 9.9 × 1099

Question 16

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

Accepted Answer

A)  -0.18 V 
B)  0.18 V 
C)  1.28 V 
D)  1.66 V 
E)  2.12 V 
A)  -0.18 V 
B)  0.18 V 
C)  1.28 V 
D)  1.66 V 
E)  2.12 V

Question 17

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

Accepted Answer

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) 
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)

Question 18

Consider the following redox equation Mn(OH)2(s) + MnO4(aq) → MnO42-(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?

Accepted Answer

A)  4, reactant side 
B)  4, product side 
C)  6, reactant side 
D)  6, product side 
E)  None of these choices are correct. 
A)  4, reactant side 
B)  4, product side 
C)  6, reactant side 
D)  6, product side 
E)  None of these choices are correct.

Question 19

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

Accepted Answer

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) 
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)

Question 20

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) → 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) 
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)

Exam 21: Electrochemistry Chemical Change and Electrical Work

A battery is considered "dead" when

Consider the reaction CuO(s) + H2(g) → Cu(s) + H2O(l) In this reaction, which substances are the oxidant and reductant, respectively?

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

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)

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.

Electrolytic cells utilize electrical energy to drive nonspontaneous redox reactions.

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

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

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)

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)

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)

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)62-(aq) + Bi(s) (basic solution)

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

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)

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

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

Consider the following redox equation Mn(OH)2(s) + MnO4(aq) → MnO42-(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?

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

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?

Keys to Studying Chemistry Definitions, Units, and Problem Solving

The Components of Matter

Stoichiometry of Formulas and Equations

Three Major Classes of Chemical Reactions

Gases and the Kinetic-Molecular Theory

Thermochemistry Energy Flow and Chemical Change

Quantum Theory and Atomic Structure

Electron Configuration and Chemical Periodicity

Models of Chemical Bonding

The Shapes of Molecules

Theories of Covalent Bonding

Intermolecular Forces Liquids, Solids, and Phase Changes

The Properties of Mixtures Solutions and Colloids

Periodic Patterns in the Main-Group Elements

Organic Compounds and the Atomic Properties of Carbon

Kinetics Rates and Mechanisms of Chemical Reactions

Equilibrium the Extent of Chemical Reactions

Acid-Base Equilibria

Ionic Equilibria in Aqueous Systems

Thermodynamics Entropy, Free Energy, and Reaction Direction

The Elements in Nature and Industry

Transition Elements and Their Coordination Compounds

Nuclear Reactions and Their Applications

Filters

Consider the reaction CuO(s) + H₂(g) → Cu(s) + H₂O(l) In this reaction, which substances are the oxidant and reductant, respectively?

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?

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)

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.

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

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

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)

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)

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 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

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)

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

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 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?