Question 1

For an electrolytic cell,

Accepted Answer

A) E is negative and ΔG is negative for the cell reaction. 
B) E is negative and ΔG is positive for the cell reaction. 
C) E is positive and ΔG is negative for the cell reaction. 
D) E is zero and ΔG is positive for the cell reaction. 
A) E is negative and ΔG is negative for the cell reaction. 
B) E is negative and ΔG is positive for the cell reaction. 
C) E is positive and ΔG is negative for the cell reaction. 
D) E is zero and ΔG is positive for the cell reaction.

Question 2

Reduction half-reactions with corresponding standard half-cell potentials are shown below.
Ag+(aq)+ 1 e- → Ag(s)E° = +0.80 V
Zn2+(aq)+ 2 e- → Zn(s)E° = -0.76 V
Mg2+(aq)+ 2 e- → Mg(s)E° = -2.37 V
Of the species above,the strongest oxidizing agent is ________,and the strongest reducing agent is ________.

Accepted Answer

Question 3

The Hall-Heroult process for the production of aluminum involves the electrolysis of

Accepted Answer

A) an aqueous solution of Al(NO3)3. 
B) molten Al2O3. 
C) molten cryolite,Na3AlF6. 
D) a molten mixture of Al2O3 and Na3AlF6. 
A) an aqueous solution of Al(NO3)3. 
B) molten Al2O3. 
C) molten cryolite,Na3AlF6. 
D) a molten mixture of Al2O3 and Na3AlF6.

Question 4

Which battery does not use MnO2(s)as a cell reactant?

Accepted Answer

A) an alkaline cell 
B) an alkaline dry cell 
C) a lithium battery 
D) a nickel-metal hydride battery 
A) an alkaline cell 
B) an alkaline dry cell 
C) a lithium battery 
D) a nickel-metal hydride battery

Question 5

When the equation below is balanced in basic solution using the smallest whole numbers,the coefficient in front of the OH-(aq)is ________.
CN-(aq)+ MnO4-(aq)→ CNO-(aq)+ MnO2(s)

Accepted Answer

Question 6

A steel pipe can be protected from corrosion by attaching the pipe to a piece of magnesium because

Accepted Answer

A) magnesium forms a tight oxide coating. 
B) magnesium is more easily oxidized than iron. 
C) magnesium is inert. 
D) magnesium and steel form a corrosion resistant alloy. 
A) magnesium forms a tight oxide coating. 
B) magnesium is more easily oxidized than iron. 
C) magnesium is inert. 
D) magnesium and steel form a corrosion resistant alloy.

Question 7

What is least easily oxidized?

Accepted Answer

A) Al 
B) Fe 
C) Mg 
D) Zn 
A) Al 
B) Fe 
C) Mg 
D) Zn

Question 8

Which of the following terms can be used to describe an electrochemical cell in which a spontaneous chemical reaction generates an electric current? I.an electrolytic cell
II.a galvanic cell
III.a voltaic cell

Accepted Answer

A) only I 
B) only II 
C) only III 
D) II and III 
A) only I 
B) only II 
C) only III 
D) II and III

Question 9

Which of the following statements concerning a lithium battery is false?

Accepted Answer

A) A lithium battery is rechargeable. 
B) A lithium battery has a relatively high voltage,due in part to the high oxidation potential of lithium. 
C) It takes a small mass of lithium to provide one mole of electrons in the cell reaction. 
D) The cell reaction produces toxic mercury,so the batteries should be recycled. 
A) A lithium battery is rechargeable. 
B) A lithium battery has a relatively high voltage,due in part to the high oxidation potential of lithium. 
C) It takes a small mass of lithium to provide one mole of electrons in the cell reaction. 
D) The cell reaction produces toxic mercury,so the batteries should be recycled.

Question 10

-Is the cell shown above a galvanic or an electrolytic cell? Which is the anode and which is the cathode?

Accepted Answer

A) Electrolytic cell;electrode x is the anode and electrode y is the cathode. 
B) Electrolytic cell;electrode y is the anode and electrode x is the cathode. 
C) Galvanic cell;electrode x is the anode and electrode y is the cathode. 
D) Galvanic cell;electrode y is the anode and electrode x is the cathode. 
A) Electrolytic cell;electrode x is the anode and electrode y is the cathode. 
B) Electrolytic cell;electrode y is the anode and electrode x is the cathode. 
C) Galvanic cell;electrode x is the anode and electrode y is the cathode. 
D) Galvanic cell;electrode y is the anode and electrode x is the cathode.

Question 11

According to the balanced chemical equation 5 H2C2O4(aq)+ 2 MnO4-(aq)+ 6 H+(aq)→ 10 CO2(g)+ 2 Mn2+(aq)+ 8 H2O(l)
0.3500 grams of oxalic acid,H2C2O4 will react with ________ mL of 0.100 M potassium permanganate,KMnO4 solution.

Accepted Answer

A) 15.5 mL 
B) 38.9 mL 
C) 77.7 mL 
D) 97.2 mL 
A) 15.5 mL 
B) 38.9 mL 
C) 77.7 mL 
D) 97.2 mL

Question 12

The standard cell potential for the following galvanic cell is 1.21 V.
Al(s)|Al3+(aq)||Fe2+(aq)|Fe(s)
When [Al3+] = 0.10 M and [Fe2+] = 0.10 M,will the cell potential at 25°C be less than,the same as,or greater than 1.21 V?

Accepted Answer

Question 13

The iron content of foods can be determined by dissolving them in acid (forming Fe3+),reducing the iron(III)to iron(II),and titrating with cerium(IV): Fe2+(aq)+ Ce4+(aq)→ Fe3+(aq)+ Ce3+(aq).
Identify the two half-reactions in the above reaction.

Accepted Answer

A) oxidation half-reaction reduction half-reaction
Fe2+(aq)+ e-→ Fe3+(aq)Ce4+(aq)→ Ce3+(aq)+ e- 
B) oxidation half-reaction reduction half-reaction
Fe2+(aq)→ Fe3+(aq)+ e- Ce4+(aq)+ e- → Ce3+(aq) 
C) oxidation half-reaction reduction half-reaction
Ce4+(aq)+ e- → Ce3+(aq)Fe2+(aq)→ Fe3+(aq)+ e- 
D) oxidation half-reaction reduction half-reaction
Ce4+(aq)→ Ce3+(aq)+ e- Fe2+(aq)+ e- → Fe3+(aq) 
A) oxidation half-reaction reduction half-reaction
Fe2+(aq)+ e-→ Fe3+(aq)Ce4+(aq)→ Ce3+(aq)+ e- 
B) oxidation half-reaction reduction half-reaction
Fe2+(aq)→ Fe3+(aq)+ e- Ce4+(aq)+ e- → Ce3+(aq) 
C) oxidation half-reaction reduction half-reaction
Ce4+(aq)+ e- → Ce3+(aq)Fe2+(aq)→ Fe3+(aq)+ e- 
D) oxidation half-reaction reduction half-reaction
Ce4+(aq)→ Ce3+(aq)+ e- Fe2+(aq)+ e- → Fe3+(aq)

Question 14

A salt bridge is used to

Accepted Answer

A) provide reactants in a fuel cell. 
B) determine the direction of the cell reaction. 
C) control whether the cell is electrolytic. 
D) allow the ion flow necessary for cell neutrality. 
A) provide reactants in a fuel cell. 
B) determine the direction of the cell reaction. 
C) control whether the cell is electrolytic. 
D) allow the ion flow necessary for cell neutrality.

Question 15

Calculate the value of the reaction quotient,Q,for the galvanic cell expressed using shorthand notation below.Use the balanced chemical equation that has the smallest whole number stoichiometric coefficients. Zn(s)∣ Zn2+(aq,0.0.0400 M)∣∣ Ag+(aq,1.25 M)∣ Ag(s)

Accepted Answer

A) 39.0 
B) 31.2 
C) 3.20 × 10-2 
D) 2.56 × 10-2 
A) 39.0 
B) 31.2 
C) 3.20 × 10-2 
D) 2.56 × 10-2

Question 16

In the unbalanced equation shown below how many moles of electrons are transferred per mole of reducing agent? C2O42- (aq)+ MnO4-(aq)→ CO2(aq)+ Mn2+(aq)

Accepted Answer

A) 3 
B) 2 
C) 5 
D) 12 
A) 3 
B) 2 
C) 5 
D) 12

Question 17

What are the coefficients in front of Ni(s)and O3(g)when the following equation is balanced in a basic solution? ________ Ni(s)+ ________ O3(g)→ ________ Ni2O3(s)+ ________ O2(g)

Accepted Answer

A) 2,2 
B) 2,3 
C) 3,2 
D) 3,4 
A) 2,2 
B) 2,3 
C) 3,2 
D) 3,4

Question 18

Based on the balanced chemical equation shown below,what volume of 0.250 M K2S2O3(aq) is needed to completely react with 12.44 mL of 0.125 M KI3(aq)? 2 S2O32-(aq)+ I3-(aq)→ S4O62-(aq)+ 3 I-(aq)

Accepted Answer

A) 3.11 mL 
B) 6.22 mL 
C) 12.4 mL 
D) 49.8 mL 
A) 3.11 mL 
B) 6.22 mL 
C) 12.4 mL 
D) 49.8 mL

Question 19

Consider the galvanic cell shown below.  
-What is the quantitative change in the cell voltage on increasing the ion concentration in the cathode compartment by a factor of 10?

Accepted Answer

A) +0.03 V 
B) +0.02 V 
C) -0.02 V 
D) -0.03 V 
A) +0.03 V 
B) +0.02 V 
C) -0.02 V 
D) -0.03 V

Question 20

Which of the following statements concerning the rusting of iron is false?

Accepted Answer

A) The oxidation site can occur at a different place on the metal surface than the reduction site. 
B) The metal is reduced. 
C) The rusting of iron requires both oxygen and water. 
D) Salt increases the rate of corrosion by providing ions to carry the current. 
A) The oxidation site can occur at a different place on the metal surface than the reduction site. 
B) The metal is reduced. 
C) The rusting of iron requires both oxygen and water. 
D) Salt increases the rate of corrosion by providing ions to carry the current.

Exam 18: Electrochemistry

For an electrolytic cell,

The Hall-Heroult process for the production of aluminum involves the electrolysis of

Which battery does not use MnO2(s)as a cell reactant?

When the equation below is balanced in basic solution using the smallest whole numbers,the coefficient in front of the OH-(aq)is ________. CN-(aq)+ MnO4-(aq)→ CNO-(aq)+ MnO2(s)

A steel pipe can be protected from corrosion by attaching the pipe to a piece of magnesium because

What is least easily oxidized?

Which of the following terms can be used to describe an electrochemical cell in which a spontaneous chemical reaction generates an electric current? I.an electrolytic cell II.a galvanic cell III.a voltaic cell

Which of the following statements concerning a lithium battery is false?

-Is the cell shown above a galvanic or an electrolytic cell? Which is the anode and which is the cathode?

According to the balanced chemical equation 5 H2C2O4(aq)+ 2 MnO4-(aq)+ 6 H+(aq)→ 10 CO2(g)+ 2 Mn2+(aq)+ 8 H2O(l) 0.3500 grams of oxalic acid,H2C2O4 will react with ________ mL of 0.100 M potassium permanganate,KMnO4 solution.

The standard cell potential for the following galvanic cell is 1.21 V. Al(s)|Al3+(aq)||Fe2+(aq)|Fe(s) When [Al3+] = 0.10 M and [Fe2+] = 0.10 M,will the cell potential at 25°C be less than,the same as,or greater than 1.21 V?

The iron content of foods can be determined by dissolving them in acid (forming Fe3+),reducing the iron(III)to iron(II),and titrating with cerium(IV): Fe2+(aq)+ Ce4+(aq)→ Fe3+(aq)+ Ce3+(aq). Identify the two half-reactions in the above reaction.

A salt bridge is used to

Calculate the value of the reaction quotient,Q,for the galvanic cell expressed using shorthand notation below.Use the balanced chemical equation that has the smallest whole number stoichiometric coefficients. Zn(s)∣ Zn2+(aq,0.0.0400 M)∣∣ Ag+(aq,1.25 M)∣ Ag(s)

In the unbalanced equation shown below how many moles of electrons are transferred per mole of reducing agent? C2O42- (aq)+ MnO4-(aq)→ CO2(aq)+ Mn2+(aq)

What are the coefficients in front of Ni(s)and O3(g)when the following equation is balanced in a basic solution? ________ Ni(s)+ ________ O3(g)→ ________ Ni2O3(s)+ ________ O2(g)

Based on the balanced chemical equation shown below,what volume of 0.250 M K2S2O3(aq) is needed to completely react with 12.44 mL of 0.125 M KI3(aq)? 2 S2O32-(aq)+ I3-(aq)→ S4O62-(aq)+ 3 I-(aq)

Consider the galvanic cell shown below. -What is the quantitative change in the cell voltage on increasing the ion concentration in the cathode compartment by a factor of 10?

Which of the following statements concerning the rusting of iron is false?

Chemical Tools: Experimentation and Measurement

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Mass Relationships in Chemical Reactions

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Periodicity and the Electronic Structure of Atoms

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Thermochemistry: Chemical Energy

Gases: Their Properties and Behavior

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Nuclear Chemistry

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Filters

Which battery does not use MnO₂(s)as a cell reactant?

When the equation below is balanced in basic solution using the smallest whole numbers,the coefficient in front of the OH^-(aq)is ________. CN^-(aq)+ MnO₄^-(aq)→ CNO^-(aq)+ MnO₂(s)

According to the balanced chemical equation 5 H₂C₂O₄(aq)+ 2 MnO₄^-(aq)+ 6 H⁺(aq)→ 10 CO₂(g)+ 2 Mn²⁺(aq)+ 8 H₂O(l) 0.3500 grams of oxalic acid,H₂C₂O₄ will react with ________ mL of 0.100 M potassium permanganate,KMnO₄ solution.

The standard cell potential for the following galvanic cell is 1.21 V. Al(s)|Al³⁺(aq)||Fe²⁺(aq)|Fe(s) When [Al³⁺] = 0.10 M and [Fe²⁺] = 0.10 M,will the cell potential at 25°C be less than,the same as,or greater than 1.21 V?

The iron content of foods can be determined by dissolving them in acid (forming Fe³⁺),reducing the iron(III)to iron(II),and titrating with cerium(IV): Fe²⁺(aq)+ Ce⁴⁺(aq)→ Fe³⁺(aq)+ Ce³⁺(aq). Identify the two half-reactions in the above reaction.

Calculate the value of the reaction quotient,Q,for the galvanic cell expressed using shorthand notation below.Use the balanced chemical equation that has the smallest whole number stoichiometric coefficients. Zn(s)∣ Zn²⁺(aq,0.0.0400 M)∣∣ Ag⁺(aq,1.25 M)∣ Ag(s)

In the unbalanced equation shown below how many moles of electrons are transferred per mole of reducing agent? C₂O₄2- (aq)+ MnO₄^-(aq)→ CO₂(aq)+ Mn²⁺(aq)

What are the coefficients in front of Ni(s)and O₃(g)when the following equation is balanced in a basic solution? Ni(s)+ O₃(g)→ Ni₂O₃(s)+ O₂(g)

Based on the balanced chemical equation shown below,what volume of 0.250 M K₂S₂O₃₍_aq₎ is needed to completely react with 12.44 mL of 0.125 M KI₃(aq)? 2 S₂O₃^2-(aq)+ I₃^-(aq)→ S₄O₆^2-(aq)+ 3 I^-(aq)