Question 1

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 2

Identify the location of oxidation in an electrochemical cell.

Accepted Answer

A)  the anode 
B)  the cathode 
C)  the electrode 
D)  the salt bridge 
E)  the socket 
A)  the anode 
B)  the cathode 
C)  the electrode 
D)  the salt bridge 
E)  the socket

Question 3

Balance the following redox reaction if it occurs in basic solution.What are the coefficients in front of Br2 and OH⁻ in the balanced reaction?
Br2(l)→ BrO3⁻(aq)+ Br⁻(aq)

Accepted Answer

A)  Br2 = 1, OH⁻ = 2 
B)  Br2 = 2, OH⁻ = 5 
C)  Br2 = 3, OH⁻ = 3 
D)  Br2 = 3, OH⁻ = 6 
E)  Br2 = 1, OH⁻ = 6 
A)  Br2 = 1, OH⁻ = 2 
B)  Br2 = 2, OH⁻ = 5 
C)  Br2 = 3, OH⁻ = 3 
D)  Br2 = 3, OH⁻ = 6 
E)  Br2 = 1, OH⁻ = 6

Question 4

What element is being reduced in the following redox reaction?
C3H8O2(aq)+ KMnO4(aq)→ C3H2O4K2(aq)+ MnO2(aq)

Accepted Answer

A)  C 
B)  H 
C)  O 
D)  K 
E)  Mn 
A)  C 
B)  H 
C)  O 
D)  K 
E)  Mn

Question 5

Balance the following redox reaction if it occurs in basic solution.What are the coefficients in front of SO32- and MnO4⁻ in the balanced reaction?
SO32-(aq)+ MnO4⁻(aq)→ SO42-(aq)+ MnO2(s)

Accepted Answer

A)  SO32- = 2, MnO4⁻ = 3 
B)  SO32- = 1, MnO4⁻ = 1 
C)  SO32- = 4, MnO4⁻ = 2 
D)  SO32- = 2, MnO4⁻ = 5 
E)  SO32- = 3, MnO4⁻ = 2 
A)  SO32- = 2, MnO4⁻ = 3 
B)  SO32- = 1, MnO4⁻ = 1 
C)  SO32- = 4, MnO4⁻ = 2 
D)  SO32- = 2, MnO4⁻ = 5 
E)  SO32- = 3, MnO4⁻ = 2

Question 6

A voltaic cell is constructed with two Zn2+-Zn electrodes,where the half-reaction is Zn2+ + 2e- → Zn(s)E° = -0.763 V
The concentrations of zinc ion in the two compartments are 5.50 M and 1.95 × 10-2 M,respectively.The cell emf is ________ V.

Accepted Answer

A)  -2.71 × 10-3 
B)  -215 
C)  0.0725 
D)  0.145 
E)  -0.759 
A)  -2.71 × 10-3 
B)  -215 
C)  0.0725 
D)  0.145 
E)  -0.759

Question 7

The standard cell potential (E°)of a voltaic cell constructed using the cell reaction below is 0.76 V: Zn(s)+ 2H+(aq)→ Zn2+(aq)+ H2(g)
With   = 1.0 atm and [Zn2+] = 1.0 M,the cell potential is 0.53 V.The concentration of H+ in the cathode compartment is ________ M.

Accepted Answer

A)  1.3 × 10-4 
B)  1.7 × 10-8 
C)  1.1 × 10-2 
D)  7.7 × 103 
E)  1.3 × 10-11 
A)  1.3 × 10-4 
B)  1.7 × 10-8 
C)  1.1 × 10-2 
D)  7.7 × 103 
E)  1.3 × 10-11

Question 8

Predict the species that will be reduced first if the following mixture of molten salts 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 9

CuHow many electrons are transferred in the following reaction? (The reaction is unbalanced.)
V5+(aq)+ Mg(s)→ V(s)+ Mg2+(aq)

Accepted Answer

A)  1 
B)  2 
C)  4 
D)  5 
E)  10 
A)  1 
B)  2 
C)  4 
D)  5 
E)  10

Question 10

What element is being reduced in the following redox reaction?
MnO4⁻(aq)+ H2C2O4(aq)→ Mn2+(aq)+ CO2(g)

Accepted Answer

A)  C 
B)  O 
C)  Mn 
D)  H 
A)  C 
B)  O 
C)  Mn 
D)  H

Question 11

Which of the following is the weakest reducing agent?

Accepted Answer

A)  Cl2(l) 
B)  ClO2-(aq) 
C)  Ag(s) 
D)  I⁻(aq) 
E)  Au(s) 
A)  Cl2(l) 
B)  ClO2-(aq) 
C)  Ag(s) 
D)  I⁻(aq) 
E)  Au(s)

Question 12

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25°C. Cu(s)∣ Cu2+(aq,0.0032 M)   Cu2+(aq,4.48 M)∣ Cu(s)

Accepted Answer

A)  0.00 V 
B)  +0.093 V 
C)  +0.34 V 
D)  +0.186 V 
E)  +0.052 V 
A)  0.00 V 
B)  +0.093 V 
C)  +0.34 V 
D)  +0.186 V 
E)  +0.052 V

Question 13

Explain the significance of the standard hydrogen electrode (SHE)in the tabulation of standard reduction potentials of other species.

Accepted Answer

The SHE is used to construct an electroc

Question 14

How many seconds are required to produce 4.00 g of aluminum metal from the electrolysis of molten AlCl3 with an electrical current of 15.0 A?

Accepted Answer

A)  21.6 
B)  7.20 
C)  9.53 × 102 
D)  2.32 × 105 
E)  2.86 × 103 
A)  21.6 
B)  7.20 
C)  9.53 × 102 
D)  2.32 × 105 
E)  2.86 × 103

Question 15

A cell consists of a Sn4+|| Sn2+ half-cell and a Fe3+ || Fe2+.If the Sn4+|| Sn2+ half-cell standard cell functions as the cathode,what is the standard reduction potential for the cell?

Accepted Answer

A)  - 0.921V 
B)  - 0.621 V 
C)  + 0.621V 
D)  + 0.921V 
A)  - 0.921V 
B)  - 0.621 V 
C)  + 0.621V 
D)  + 0.921V

Question 16

Consider the galvanic cell,   Which one of the following changes to the cell would cause the cell potential to increase (i.e.,become more positive)?

Accepted Answer

A)  increase the [Zn2+] concentration 
B)  increase the [Pb2+] concentration 
C)  increase the mass of Zn(s) 
D)  decrease the mass of Zn(s) 
A)  increase the [Zn2+] concentration 
B)  increase the [Pb2+] concentration 
C)  increase the mass of Zn(s) 
D)  decrease the mass of Zn(s)

Question 17

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25°C. Mn(s)∣ Mn2+(aq,1.28 M)   Ag+(aq,0.000837 M)∣ Ag(s)

Accepted Answer

A)  1.98 V 
B)  -1.28 V 
C)  0.00 V 
D)  1.79 V 
E)  -0.84 V 
A)  1.98 V 
B)  -1.28 V 
C)  0.00 V 
D)  1.79 V 
E)  -0.84 V

Question 18

Determine the redox reaction represented by the following cell notation. Mn(s)∣ Mn2+(aq)   Cu2+(aq)∣ Cu(s)

Accepted Answer

A)  Cu(s) + Mn2+(aq) → Mn(s) + Cu2+(aq) 
B)  Mn(s) + Cu2+(aq) → Cu(s) + Mn2+(aq) 
C)  2 Mn(s) + Cu2+(aq) → Cu(s) + 2 Mn2+(aq) 
D)  2 Cu(s) + Mn2+(aq) → Mn(s) + 2 Cu2+(aq) 
E)  3 Mn(s) + 2 Cu2+(aq) → 2 Cu(s) + 3 Mn2+(aq) 
A)  Cu(s) + Mn2+(aq) → Mn(s) + Cu2+(aq) 
B)  Mn(s) + Cu2+(aq) → Cu(s) + Mn2+(aq) 
C)  2 Mn(s) + Cu2+(aq) → Cu(s) + 2 Mn2+(aq) 
D)  2 Cu(s) + Mn2+(aq) → Mn(s) + 2 Cu2+(aq) 
E)  3 Mn(s) + 2 Cu2+(aq) → 2 Cu(s) + 3 Mn2+(aq)

Question 19

Balance the following redox reaction.What are the coefficients in front of H2O and NO in the balanced reaction?
Zn(s)+ HNO3(aq)→ Zn2+(aq)+ NO(g)

Accepted Answer

A)  H2O =4, NO = 2 
B)  H2O =8, NO = 6 
C)  H2O =1, NO = 3 
D)  H2O =10, NO = 7 
E)  H2O =5, NO = 9 
A)  H2O =4, NO = 2 
B)  H2O =8, NO = 6 
C)  H2O =1, NO = 3 
D)  H2O =10, NO = 7 
E)  H2O =5, NO = 9

Question 20

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25°C. Mg(s)∣ Mg2+(aq,2.74 M)   Cu2+(aq,0.0033 M)∣ Cu(s)

Accepted Answer

A)  -2.80 V 
B)  +2.62 V 
C)  +2.71 V 
D)  +2.12 V 
E)  -1.94 V 
A)  -2.80 V 
B)  +2.62 V 
C)  +2.71 V 
D)  +2.12 V 
E)  -1.94 V

Exam 20: Electrochemistry

Identify the battery that is in most automobiles.

Identify the location of oxidation in an electrochemical cell.

Balance the following redox reaction if it occurs in basic solution.What are the coefficients in front of Br2 and OH⁻ in the balanced reaction? Br2(l)→ BrO3⁻(aq)+ Br⁻(aq)

What element is being reduced in the following redox reaction? C3H8O2(aq)+ KMnO4(aq)→ C3H2O4K2(aq)+ MnO2(aq)

Balance the following redox reaction if it occurs in basic solution.What are the coefficients in front of SO32- and MnO4⁻ in the balanced reaction? SO32-(aq)+ MnO4⁻(aq)→ SO42-(aq)+ MnO2(s)

A voltaic cell is constructed with two Zn2+-Zn electrodes,where the half-reaction is Zn2+ + 2e- → Zn(s)E° = -0.763 V The concentrations of zinc ion in the two compartments are 5.50 M and 1.95 × 10-2 M,respectively.The cell emf is ________ V.

The standard cell potential (E°)of a voltaic cell constructed using the cell reaction below is 0.76 V: Zn(s)+ 2H+(aq)→ Zn2+(aq)+ H2(g) With = 1.0 atm and [Zn2+] = 1.0 M,the cell potential is 0.53 V.The concentration of H+ in the cathode compartment is ________ M.

Predict the species that will be reduced first if the following mixture of molten salts undergoes electrolysis. Na+,Ca2+,Cl⁻,Br⁻,F⁻

CuHow many electrons are transferred in the following reaction? (The reaction is unbalanced.) V5+(aq)+ Mg(s)→ V(s)+ Mg2+(aq)

What element is being reduced in the following redox reaction? MnO4⁻(aq)+ H2C2O4(aq)→ Mn2+(aq)+ CO2(g)

Which of the following is the weakest reducing agent?

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25°C. Cu(s)∣ Cu2+(aq,0.0032 M) Cu2+(aq,4.48 M)∣ Cu(s)

Explain the significance of the standard hydrogen electrode (SHE)in the tabulation of standard reduction potentials of other species.

How many seconds are required to produce 4.00 g of aluminum metal from the electrolysis of molten AlCl3 with an electrical current of 15.0 A?

A cell consists of a Sn4+|| Sn2+ half-cell and a Fe3+ || Fe2+.If the Sn4+|| Sn2+ half-cell standard cell functions as the cathode,what is the standard reduction potential for the cell?

Consider the galvanic cell, Which one of the following changes to the cell would cause the cell potential to increase (i.e.,become more positive)?

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25°C. Mn(s)∣ Mn2+(aq,1.28 M) Ag+(aq,0.000837 M)∣ Ag(s)

Determine the redox reaction represented by the following cell notation. Mn(s)∣ Mn2+(aq) Cu2+(aq)∣ Cu(s)

Balance the following redox reaction.What are the coefficients in front of H2O and NO in the balanced reaction? Zn(s)+ HNO3(aq)→ Zn2+(aq)+ NO(g)

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25°C. Mg(s)∣ Mg2+(aq,2.74 M) Cu2+(aq,0.0033 M)∣ Cu(s)

Essentials: Units, Measurements, and Problem Solving

Atoms

The Quantum Mechanical Model of the Atom

Periodic Properties of the Elements

Molecules and Compounds

Chemical Bonding I

Chemical Bonding Ii

Chemical Reactions and Chemical Quantities

Introduction to Solutions and Aqueous Reactions

Thermochemistry

Gases

Liquids, Solids, and Intermolecular Forces

Crystalline Solids and Modern Materials

Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Free Energy and Thermodynamics

Radioactivity and Nuclear Chemistry

Organic Chemistry

Transition Metals and Coordination Compounds

Filters

Balance the following redox reaction if it occurs in basic solution.What are the coefficients in front of Br₂and OH⁻ in the balanced reaction? Br₂(l)→ BrO₃⁻(aq)+ Br⁻(aq)

What element is being reduced in the following redox reaction? C₃H₈O₂(aq)+ KMnO₄(aq)→ C₃H₂O₄K₂(aq)+ MnO₂(aq)

Balance the following redox reaction if it occurs in basic solution.What are the coefficients in front of SO₃^2-and MnO₄⁻ in the balanced reaction? SO₃^2-(aq)+ MnO₄⁻(aq)→ SO₄^2-(aq)+ MnO₂(s)

A voltaic cell is constructed with two Zn²⁺-Zn electrodes,where the half-reaction is Zn²⁺ + 2e^- → Zn(s)E° = -0.763 V The concentrations of zinc ion in the two compartments are 5.50 M and 1.95 × 10^-2 M,respectively.The cell emf is ________ V.

The standard cell potential (E°)of a voltaic cell constructed using the cell reaction below is 0.76 V: Zn(s)+ 2H⁺(aq)→ Zn²⁺(aq)+ H₂(g) With = 1.0 atm and [Zn²⁺] = 1.0 M,the cell potential is 0.53 V.The concentration of H⁺ in the cathode compartment is ________ M.

Predict the species that will be reduced first if the following mixture of molten salts undergoes electrolysis. Na⁺,Ca²⁺,Cl⁻,Br⁻,F⁻

CuHow many electrons are transferred in the following reaction? (The reaction is unbalanced.) V⁵⁺(aq)+ Mg(s)→ V(s)+ Mg²⁺(aq)

What element is being reduced in the following redox reaction? MnO₄⁻(aq)+ H₂C₂O₄(aq)→ Mn²⁺(aq)+ CO₂(g)

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25°C. Cu(s)∣ Cu²⁺(aq,0.0032 M) Cu²⁺(aq,4.48 M)∣ Cu(s)

How many seconds are required to produce 4.00 g of aluminum metal from the electrolysis of molten AlCl₃ with an electrical current of 15.0 A?

A cell consists of a Sn⁴⁺|| Sn²⁺half-cell and a Fe³⁺ || Fe²⁺.If the Sn⁴⁺|| Sn²⁺ half-cell standard cell functions as the cathode,what is the standard reduction potential for the cell?

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25°C. Mn(s)∣ Mn²⁺(aq,1.28 M) Ag⁺(aq,0.000837 M)∣ Ag(s)

Determine the redox reaction represented by the following cell notation. Mn(s)∣ Mn²⁺(aq) Cu²⁺(aq)∣ Cu(s)

Balance the following redox reaction.What are the coefficients in front of H₂O and NO in the balanced reaction? Zn(s)+ HNO₃(aq)→ Zn²⁺(aq)+ NO(g)

Calculate the cell potential for the following reaction that takes place in an electrochemical cell at 25°C. Mg(s)∣ Mg²⁺(aq,2.74 M) Cu²⁺(aq,0.0033 M)∣ Cu(s)