Question 1

In a half reaction the amount of a substance that is reduced or oxidized is directly proportional to the number of electrons generated in the cell.

Accepted Answer

A) True 
 B)False  True

Question 2

The purpose of the salt bridge in an electrochemical cell is to .

Accepted Answer

A)  provide a source of ions to react at the anode and cathode. 
B)  maintain electrical neutrality in the half- cells via migration of ions. 
C)  provide a means for electrons to travel from the anode to the cathode. 
D)  provide a means for electrons to travel from the cathode to the anode. 
E)  provide oxygen to facilitate oxidation at the anode. 
A)  provide a source of ions to react at the anode and cathode. 
B)  maintain electrical neutrality in the half- cells via migration of ions. 
C)  provide a means for electrons to travel from the anode to the cathode. 
D)  provide a means for electrons to travel from the cathode to the anode. 
E)  provide oxygen to facilitate oxidation at the anode. B

Question 3

In a lead- acid battery, the electrodes are consumed. In this battery,

Accepted Answer

A)  the anode is PbSO4. 
B)  the cathode is PbSO4. 
C)  the anode is PbO2. 
D)  the cathode is Pb. 
E)  the anode is Pb. 
A)  the anode is PbSO4. 
B)  the cathode is PbSO4. 
C)  the anode is PbO2. 
D)  the cathode is Pb. 
E)  the anode is Pb. E

Question 4

The balanced half- reaction in which sulfate ion is reduced to sulfite ion is a process.

Accepted Answer

A)  three- electron 
B)  one- electron 
C)  six- electron 
D)  two- electron 
E)  four- electron 
A)  three- electron 
B)  one- electron 
C)  six- electron 
D)  two- electron 
E)  four- electron

Question 5

Which one of the following reactions is a redox reaction?

Accepted Answer

A)  H2O + NaCl - NaOH + HCl 
B)  NaOH + HCl - NaCl + H2O 
C)  Pb2+ + 2Cl- - PbCl2 
D)  AgNO3 + HCl - HNO3 + AgCl 
E)  None of the above is a redox reaction. 
A)  H2O + NaCl - NaOH + HCl 
B)  NaOH + HCl - NaCl + H2O 
C)  Pb2+ + 2Cl- - PbCl2 
D)  AgNO3 + HCl - HNO3 + AgCl 
E)  None of the above is a redox reaction.

Question 6

What is the coefficient of the permanganate ion when the following equation is balanced?

Accepted Answer

A)  2 
B)  1 
C)  5 
D)  3 
E)  4 
A)  2 
B)  1 
C)  5 
D)  3 
E)  4

Question 7

When iron is coated with a thin layer of zinc to protect against corrosion, the iron is said to be .

Accepted Answer

The answer of When iron is coated with a thin...

Question 8

Using Table 20.1, which substance can oxidize I- (aq) to I2 (s) ?

Accepted Answer

A)  Ag (s) 
B)  Br2 (l) 
C)  Cu2+ (aq) 
D)  Ni2+ (aq) 
E)  Br- (aq) 
A)  Ag (s) 
B)  Br2 (l) 
C)  Cu2+ (aq) 
D)  Ni2+ (aq) 
E)  Br- (aq)

Question 9

What is the oxidation number of manganese in the Mn O 1- ion?

Accepted Answer

A)  +7 
B)  +5 
C)  +4 
D)  +1 
E)  +2
  
A)  +7 
B)  +5 
C)  +4 
D)  +1 
E)  +2

Question 10

1V = .

Accepted Answer

A)  1 C/J 
B)  1 J/s 
C)  1 J/C 
D)  96485 C 
E)  1 amp · s 
A)  1 C/J 
B)  1 J/s 
C)  1 J/C 
D)  96485 C 
E)  1 amp · s

Question 11

How many seconds are required to produce 1.0 g of silver metal by the electrolysis of a AgNO3 solution using a current of 30 amps _ ?

Accepted Answer

A)  3.7 × 10- 5  
B)  3.2 × 103  
C)  2.7 × 104  
D)  60 
E)  30 
A)  3.7 × 10- 5  
B)  3.2 × 103  
C)  2.7 × 104  
D)  60 
E)  30

Question 12

The standard cell potential (E°cell) for the voltaic cell based on the reaction below is V.

Accepted Answer

A)  +1.57 
B)  - 1.45 
C)  +3.05 
D)  +2.99 
E)  +1.51 
A)  +1.57 
B)  - 1.45 
C)  +3.05 
D)  +2.99 
E)  +1.51

Question 13

How many grams of copper will be plated out by a current of 2.3 A applied for 25 minutes to a 0.50- M solution of copper(II) sulfate _ ?

Accepted Answer

A)  0.019 
B)  1.8 × 10- 2  
C)  1.1 
D)  2.2 
E)  0.036 
A)  0.019 
B)  1.8 × 10- 2  
C)  1.1 
D)  2.2 
E)  0.036

Question 14

electrons appear in the following half- reaction when it is balanced.

Accepted Answer

A)  4 
B)  1 
C)  2 
D)  3 
E)  6 
A)  4 
B)  1 
C)  2 
D)  3 
E)  6

Question 15

What is the anode in an alkaline battery ?

Accepted Answer

A)  Mn2O3 
B)  MnO2 
C)  KOH 
D)  Pt 
E)  Zn powder 
A)  Mn2O3 
B)  MnO2 
C)  KOH 
D)  Pt 
E)  Zn powder

Question 16

The more the value of E°red, the greater the driving force for reduction.

Accepted Answer

A)  extensive 
B)  positive 
C)  negative 
D)  endothermic 
E)  exothermic 
A)  extensive 
B)  positive 
C)  negative 
D)  endothermic 
E)  exothermic

Question 17

A voltaic cell can be constructed of the same species as long as the are different.

Accepted Answer

The answer of A voltaic cell can be constructed of...

Question 18

What is the oxidation number of manganese in MnO2?

Accepted Answer

A)  +1 
B)  +3 
C)  +4 
D)  +7 
E)  +2 
A)  +1 
B)  +3 
C)  +4 
D)  +7 
E)  +2

Question 19

Which transformation could take place at the anode of an electrochemical cell?

Accepted Answer

A)  O2 to H2O 
B)  Cr2O72-  -Cr2+ 
C)  HAsO2 to As 
D)  F2 toF- 
E)  None of the above could take place at the anode. 
A)  O2 to H2O 
B)  Cr2O72-  -Cr2+ 
C)  HAsO2 to As 
D)  F2 toF- 
E)  None of the above could take place at the anode.

Question 20

The standard cell potential (E°) of a voltaic cell constructed using the cell reaction below is 0.76 V:
 
With PH2 = 1.0 atm and [Zn2+] = 1.0 M, the cell potential is 0.66 V. The concentration of H+ in the
Cathode compartment is _ M.

Accepted Answer

A)  4.2 × 10- 4 
B)  1.0 × 10- 12 
C)  4.9 × 101 
D)  2.0 × 10- 2 
E)  1.4 × 10- 1 
A)  4.2 × 10- 4 
B)  1.0 × 10- 12 
C)  4.9 × 101 
D)  2.0 × 10- 2 
E)  1.4 × 10- 1

Exam 20: Electrochemistry

In a half reaction the amount of a substance that is reduced or oxidized is directly proportional to the number of electrons generated in the cell.

The purpose of the salt bridge in an electrochemical cell is to .

In a lead- acid battery, the electrodes are consumed. In this battery,

The balanced half- reaction in which sulfate ion is reduced to sulfite ion is a process.

Which one of the following reactions is a redox reaction?

What is the coefficient of the permanganate ion when the following equation is balanced?

When iron is coated with a thin layer of zinc to protect against corrosion, the iron is said to be .

Using Table 20.1, which substance can oxidize I- (aq) to I2 (s) ?

What is the oxidation number of manganese in the Mn O 1- ion?

1V = .

How many seconds are required to produce 1.0 g of silver metal by the electrolysis of a AgNO3 solution using a current of 30 amps _ ?

The standard cell potential (E°cell) for the voltaic cell based on the reaction below is V.

How many grams of copper will be plated out by a current of 2.3 A applied for 25 minutes to a 0.50- M solution of copper(II) sulfate _ ?

electrons appear in the following half- reaction when it is balanced.

What is the anode in an alkaline battery ?

The more the value of E°red, the greater the driving force for reduction.

A voltaic cell can be constructed of the same species as long as the are different.

What is the oxidation number of manganese in MnO2?

Which transformation could take place at the anode of an electrochemical cell?

The standard cell potential (E°) of a voltaic cell constructed using the cell reaction below is 0.76 V: With PH2 = 1.0 atm and [Zn2+] = 1.0 M, the cell potential is 0.66 V. The concentration of H+ in the Cathode compartment is _ M.

Introduction: Matter and Measurement

Atoms, Molecules, and Ions

Stoichiometry: Calculations With Chemical Formulas and Equations

Aqueous Reactions and Solution Stoichiometry

Electronic Structure of Atoms

Periodic Properties of the Elements

Basic Concepts of Chemical Bonding

Gases

Intermolecular Forces, Liquids, and Solids

Modern Materials

Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acid-Base Equilibria

Additional Aspects of Equilibria

Chemistry of the Environment

Chemical Thermodynamics

Nuclear Chemistry

Chemistry of the Nonmetals

Metals and Metallurgy

Chemistry of Coordination Compounds

The Chemistry of Life: Organic and Biological Chemistry

Filters

Using Table 20.1, which substance can oxidize I^-(aq) to I₂(s) ?

What is the oxidation number of manganese in the Mn O ¹^-ion?

How many seconds are required to produce 1.0 g of silver metal by the electrolysis of a AgNO₃ solution using a current of 30 amps _ ?

The standard cell potential (E°_cell) for the voltaic cell based on the reaction below is V.

The more the value of E°_red, the greater the driving force for reduction.

What is the oxidation number of manganese in MnO₂?

The standard cell potential (E°) of a voltaic cell constructed using the cell reaction below is 0.76 V: With P_H₂= 1.0 atm and [Zn²⁺] = 1.0 M, the cell potential is 0.66 V. The concentration of H⁺in the Cathode compartment is _ M.