Question 1

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⁻

Accepted Answer

A) Na⁺ 
B) Cl⁻ 
C) Ca2+ 
D) Br⁻ 
E) F⁻ 
A) Na⁺ 
B) Cl⁻ 
C) Ca2+ 
D) Br⁻ 
E) F⁻

Question 2

What mass of silver can be plated onto an object in 33.5 minutes at 8.70 A of current? Ag⁺(aq)+ e⁻ → Ag(s)

Accepted Answer

A) 19.6 g 
B) 0.326 g 
C) 9.78 g 
D) 3.07 g 
E) 0.102 g 
A) 19.6 g 
B) 0.326 g 
C) 9.78 g 
D) 3.07 g 
E) 0.102 g

Question 3

Identify the battery that is in most automobiles.

Accepted Answer

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

Question 4

Identify the characteristics of a spontaneous reaction.

Accepted Answer

A) ΔrG° > 0 
B) ΔE°cell cell > 0 
E) K = 0 
A) ΔrG° > 0 
B) ΔE°cell cell > 0 
E) K = 0

Question 5

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

Accepted Answer

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

Question 6

Which of the following is the strongest reducing agent?

Accepted Answer

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

Question 7

Use the provided reduction potentials to calculate ΔrG° 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

Accepted Answer

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 
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 8

A galvanic cell consists of a Ni2+/Ni half-cell and a standard hydrogen electrode. If the Ni2+/Ni half-cell standard cell functions as the anode, and the standard cell potential is 0.26 V, what is the standard reduction potential for the Ni2+/Ni half-cell?

Accepted Answer

A) -0.26 V 
B) -0.13 V 
C) +0.13 V 
D) +0.26 V 
A) -0.26 V 
B) -0.13 V 
C) +0.13 V 
D) +0.26 V

Question 9

What is the reaction at the cathode in a breathalyzer?

Accepted Answer

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. 
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 10

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

Accepted Answer

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

Question 11

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

Accepted Answer

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

Question 12

How long must a constant current of 50.0 A be passed through an electrolytic cell containing aqueous Cu2+ ions to produce 5.00 moles of copper metal?

Accepted Answer

A) 0.187 hours 
B) 0.373 hours 
C) 2.68 hours 
D) 5.36 hours 
A) 0.187 hours 
B) 0.373 hours 
C) 2.68 hours 
D) 5.36 hours

Question 13

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

Accepted Answer

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

Question 14

Balance the following redox reaction if it occurs in basic solution. What are the coefficients in front of ClO2 and H2O in the balanced reaction? H2O2(l)+ ClO2(aq)→ ClO2⁻(aq)+ O2(g)

Accepted Answer

A) ClO2 = 1, H2O = 1 
B) ClO2 = 1, H2O = 2 
C) ClO2 = 4, H2O = 3 
D) ClO2 = 4, H2O = 2 
E) ClO2 = 2, H2O = 2 
A) ClO2 = 1, H2O = 1 
B) ClO2 = 1, H2O = 2 
C) ClO2 = 4, H2O = 3 
D) ClO2 = 4, H2O = 2 
E) ClO2 = 2, H2O = 2

Question 15

What mass of aluminum can be plated onto an object in 755 minutes at 5.80 A of current?

Accepted Answer

A) 73.5 g 
B) 24.5 g 
C) 220. g 
D) 147 g 
E) 8.17 g 
A) 73.5 g 
B) 24.5 g 
C) 220. g 
D) 147 g 
E) 8.17 g

Question 16

Match the following.

-Q < K

Accepted Answer

A) E°cell cell cell > 0 
D) Ecell > 0 
E) Ecell = 0
F)Ecell = E°cell 
A) E°cell cell cell > 0 
D) Ecell > 0 
E) Ecell = 0
F)Ecell = E°cell

Question 17

What is the difference between a voltaic cell and an electrolytic cell?

Accepted Answer

A voltaic cell contains a redox reaction

Question 18

The electrolysis of molten AlCl3 for 3.25 hr with an electrical current of 15.0 A produces ________ g of aluminum metal.

Accepted Answer

A) 147 
B) 0.606 
C) 4.55 × 10-3 
D) 16.4 
E) 49.1 
A) 147 
B) 0.606 
C) 4.55 × 10-3 
D) 16.4 
E) 49.1

Question 19

Based on the following information, Cl2(g)+ 2 e- → 2Cl-(aq)E° = +1.36 V
Mg2+(aq)+ 2 e- → 2Mg(s)E° = -2.37 V
Which of the following chemical species is the strongest reducing agent?

Accepted Answer

A) Cl2(g) 
B) Mg2+(aq) 
C) Cl-(aq) 
D) Mg(s) 
A) Cl2(g) 
B) Mg2+(aq) 
C) Cl-(aq) 
D) Mg(s)

Question 20

Match the following.

-Q = K

Accepted Answer

A) E°cell cell cell > 0 
D) Ecell > 0 
E) Ecell = 0
F)Ecell = E°cell 
A) E°cell cell cell > 0 
D) Ecell > 0 
E) Ecell = 0
F)Ecell = E°cell

Exam 18: Electrochemistry

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⁻

What mass of silver can be plated onto an object in 33.5 minutes at 8.70 A of current? Ag⁺(aq)+ e⁻ → Ag(s)

Identify the battery that is in most automobiles.

Identify the characteristics of a spontaneous reaction.

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

Which of the following is the strongest reducing agent?

Use the provided reduction potentials to calculate ΔrG° 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 galvanic cell consists of a Ni2+/Ni half-cell and a standard hydrogen electrode. If the Ni2+/Ni half-cell standard cell functions as the anode, and the standard cell potential is 0.26 V, what is the standard reduction potential for the Ni2+/Ni half-cell?

What is the reaction at the cathode in a breathalyzer?

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

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

How long must a constant current of 50.0 A be passed through an electrolytic cell containing aqueous Cu2+ ions to produce 5.00 moles of copper metal?

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

Balance the following redox reaction if it occurs in basic solution. What are the coefficients in front of ClO2 and H2O in the balanced reaction? H2O2(l)+ ClO2(aq)→ ClO2⁻(aq)+ O2(g)

What mass of aluminum can be plated onto an object in 755 minutes at 5.80 A of current?

Match the following. -Q < K

What is the difference between a voltaic cell and an electrolytic cell?

The electrolysis of molten AlCl3 for 3.25 hr with an electrical current of 15.0 A produces ________ g of aluminum metal.

Based on the following information, Cl2(g)+ 2 e- → 2Cl-(aq)E° = +1.36 V Mg2+(aq)+ 2 e- → 2Mg(s)E° = -2.37 V Which of the following chemical species is the strongest reducing agent?

Match the following. -Q = K

Units of Measurement for Physical and Chemical Change

Atoms and Elements

Molecules, Compounds, and Nomenclature

Chemical Reactions and Stoichiometry

Gases

Thermochemistry

The Quantum-Mechanical Model of the Atom

Periodic Properties of the Elements

Chemical Bonding I: Lewis Theory

Chemical Bonding Ii: Molecular Shapes, Valence Bond Theory, and Molecular Orbital Theory

Liquids, Solids, and Intermolecular Forces

Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Gibbs Energy and Thermodynamics

Radioactivity and Nuclear Chemistry

Organic Chemistry I: Structures

Organic Chemistry II: Reactions

Biochemistry

Chemistry of the Nonmetals

Metals and Metallury

Transition Metals and Coordination Compounds

Filters

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⁻

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

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 galvanic cell consists of a Ni²⁺/Ni half-cell and a standard hydrogen electrode. If the Ni²⁺/Ni half-cell standard cell functions as the anode, and the standard cell potential is 0.26 V, what is the standard reduction potential for the Ni²+/Ni half-cell?

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

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

How long must a constant current of 50.0 A be passed through an electrolytic cell containing aqueous Cu²⁺ ions to produce 5.00 moles of copper metal?

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

Balance the following redox reaction if it occurs in basic solution. What are the coefficients in front of ClO₂and H₂O in the balanced reaction? H₂O₂(l)+ ClO₂(aq)→ ClO₂⁻(aq)+ O₂(g)

The electrolysis of molten AlCl₃ for 3.25 hr with an electrical current of 15.0 A produces ________ g of aluminum metal.

Based on the following information, Cl₂(g)+ 2 e^- → 2Cl^-(aq)E° = +1.36 V Mg²⁺(aq)+ 2 e^- → 2Mg(s)E° = -2.37 V Which of the following chemical species is the strongest reducing agent?