Question 1

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

Accepted Answer

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

Question 2

The loss of electrons by an element is called ________.

Accepted Answer

A) fractionation 
B) reduction 
C) disproportionation 
D) oxidation 
E) sublimation

Question 3

When the cell potential is negative in a voltaic cell,the cell reaction will not proceed spontaneously.

Accepted Answer

A) True 
 B)False

Question 4

How many kilowatt-hours of electricity are used to produce 4.50 kg of magnesium in the electrolysis of molten  with an applied emf of 5.00 V?

Accepted Answer

A) 0.0201 
B) 0.0496 
C) 12.4 
D) 49.6 
E) 24.8

Question 5

The electrode at which oxidation occurs is called the ________.

Accepted Answer

A) oxidizing agent 
B) cathode 
C) reducing agent 
D) anode 
E) voltaic cell

Question 6

What is the oxidation number of nitrogen in the NH2OH molecule?

Accepted Answer

A) -1 
B) -2 
C) -3 
D) 0 
E) +1

Question 7

The standard cell potential (E°cell)for the voltaic cell based on the reaction below is ________ V. Cr (s)+ 3Fe3+ (aq)→ 3Fe2+ (aq)+ Cr3+ (aq)

Accepted Answer

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

Question 8

Which of the following reactions is a redox reaction?
(a)K2CrO4 + BaCl2 → BaCrO4 + 2KCl
(b)Pb22+ + 2Br- → PbBr
(c)Cu + S → CuS

Accepted Answer

A) (a)only 
B) (b)only 
C) (c)only 
D) (a)and (c) 
E) (b)and (c)

Question 9

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

Accepted Answer

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

Question 10

Which element is reduced in the following reaction?
Cr2O72- + 6S2O32- + 14H+ → 2Cr3+ + 3S4O62- + 7H2O

Accepted Answer

A) H 
B) Cr 
C) O 
D) S 
E) S4O62-

Question 11

The potential (E)to move K⁺ from the extracellular fluid to the intracellular fluid necessitates work.The sign for this potential is ________.

Accepted Answer

The answer of The potential (E)to move K⁺ from the...

Question 12

The less ________ the value of E°red,the lower the driving force for reduction.

Accepted Answer

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

Question 13

The town of Natrium,West Virginia,derives its name from the sodium produced in the electrolysis of molten sodium chloride (NaCl)mined from ancient salt deposits.The number of kilowatt-hours of electricity required to produce 4.50 kg of metallic sodium from the electrolysis of molten NaCl(s)is ________ when the applied emf is 5.00 V.

Accepted Answer

A) 26.2 
B) 0.0381 
C) 0.0262 
D) 52.5 
E) 13.1

Exam 20: Electrochemistry

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

The loss of electrons by an element is called ________.

When the cell potential is negative in a voltaic cell,the cell reaction will not proceed spontaneously.

How many kilowatt-hours of electricity are used to produce 4.50 kg of magnesium in the electrolysis of molten with an applied emf of 5.00 V?

The electrode at which oxidation occurs is called the ________.

What is the oxidation number of nitrogen in the NH₂OH molecule?

The standard cell potential (E°_cell) for the voltaic cell based on the reaction below is ________ V. Cr (s) + 3Fe³⁺ (aq) → 3Fe²⁺ (aq) + Cr³⁺ (aq)

Which of the following reactions is a redox reaction? (a) K₂CrO₄ + BaCl₂ → BaCrO₄ + 2KCl (b) Pb₂²⁺ + 2Br^- → PbBr (c) Cu + S → CuS

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

Which element is reduced in the following reaction? Cr₂O₇^2- + 6S₂O₃^2- + 14H⁺ → 2Cr³⁺ + 3S₄O₆^2- + 7H₂O

The potential (E)to move K⁺ from the extracellular fluid to the intracellular fluid necessitates work.The sign for this potential is ________.

The less ________ the value of E°_red,the lower the driving force for reduction.

Exam 20: Electrochemistry

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

The loss of electrons by an element is called ________.

When the cell potential is negative in a voltaic cell,the cell reaction will not proceed spontaneously.

How many kilowatt-hours of electricity are used to produce 4.50 kg of magnesium in the electrolysis of molten with an applied emf of 5.00 V?

The electrode at which oxidation occurs is called the ________.

What is the oxidation number of nitrogen in the NH2OH molecule?

The standard cell potential (E°cell) for the voltaic cell based on the reaction below is ________ V. Cr (s) + 3Fe3+ (aq) → 3Fe2+ (aq) + Cr3+ (aq)

Which of the following reactions is a redox reaction? (a) K2CrO4 + BaCl2 → BaCrO4 + 2KCl (b) Pb22+ + 2Br- → PbBr (c) Cu + S → CuS

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

Which element is reduced in the following reaction? Cr2O72- + 6S2O32- + 14H+ → 2Cr3+ + 3S4O62- + 7H2O

The potential (E)to move K+ from the extracellular fluid to the intracellular fluid necessitates work.The sign for this potential is ________.

The less ________ the value of E°red,the lower the driving force for reduction.

What is the oxidation number of nitrogen in the NH₂OH molecule?

The standard cell potential (E°_cell) for the voltaic cell based on the reaction below is ________ V. Cr (s) + 3Fe³⁺ (aq) → 3Fe²⁺ (aq) + Cr³⁺ (aq)

Which of the following reactions is a redox reaction? (a) K₂CrO₄ + BaCl₂ → BaCrO₄ + 2KCl (b) Pb₂²⁺ + 2Br^- → PbBr (c) Cu + S → CuS

Which element is reduced in the following reaction? Cr₂O₇^2- + 6S₂O₃^2- + 14H⁺ → 2Cr³⁺ + 3S₄O₆^2- + 7H₂O

The potential (E)to move K⁺ from the extracellular fluid to the intracellular fluid necessitates work.The sign for this potential is ________.

The less ________ the value of E°_red,the lower the driving force for reduction.