Question 1

Which of the following is not an advantage in using hydrogen fuel cells rather than gasoline engines in vehicles?

Accepted Answer

A) It is a more efficient use of chemical energy. 
B) Only water is emitted as a product. 
C) Imported petroleum is replaced as the source of energy. 
D) Storage is less dangerous than the gasoline tank. 
E) Hydrogen is an abundant element. 
A) It is a more efficient use of chemical energy. 
B) Only water is emitted as a product. 
C) Imported petroleum is replaced as the source of energy. 
D) Storage is less dangerous than the gasoline tank. 
E) Hydrogen is an abundant element.

Question 2

What is the cell potential for this electrochemical cell? It consists of two compartments, labeled C1 and C2.
The temperature is 298 K.
C1 consists of a copper metal electrode immersed in a 0.30 M copper sulfate solution.
C2 consists of a copper metal electrode immersed in a 1.5 M copper sulfate solution.   ,   F1F1F1S1F1F1F10 F1F1F1S1F1F1F100.34 V

Accepted Answer

A) (F1F1F1S1F1F1F100.34 V) 
B) (F1F1F1S1F1F1F100.34 V) 
C) (F1F1F1S1F1F1F100.02 V) 
D) (F1F1F1S1F1F1F100.36 V) 
E) More information is needed to decide. 
A) (F1F1F1S1F1F1F100.34 V) 
B) (F1F1F1S1F1F1F100.34 V) 
C) (F1F1F1S1F1F1F100.02 V) 
D) (F1F1F1S1F1F1F100.36 V) 
E) More information is needed to decide.

Question 3

A NiMH battery uses ________ as the reducing agent.

Accepted Answer

A) nickel 
B) a metal hydride 
C) hydroxide 
D) hydronium ion 
E) nickel oxide 
A) nickel 
B) a metal hydride 
C) hydroxide 
D) hydronium ion 
E) nickel oxide

Question 4

A typical AA battery has a capacity of 0.500 ampere-hours (A F1F1F1S1F1F1F10 hr). How many electrons can such a battery supply?

Accepted Answer

A) 1.87 F1F1F1S1F1F1F10 1020 
B) 3.01 F1F1F1S1F1F1F10 1023 
C) 1.25 F1F1F1S1F1F1F10 1019 
D) 3.12 F1F1F1S1F1F1F10 1018 
E) 1.12 F1F1F1S1F1F1F10 1022 
A) 1.87 F1F1F1S1F1F1F10 1020 
B) 3.01 F1F1F1S1F1F1F10 1023 
C) 1.25 F1F1F1S1F1F1F10 1019 
D) 3.12 F1F1F1S1F1F1F10 1018 
E) 1.12 F1F1F1S1F1F1F10 1022

Question 5

If the free-energy change of the following voltaic cell   is F1F1F1S1F1F1F1046.3 kJ, what is the standard potential of the cell?

Accepted Answer

A) (F1F1F1S1F1F1F100.080 V) 
B) (F1F1F1S1F1F1F100.080 V) 
C) (F1F1F1S1F1F1F100.240 V) 
D) (F1F1F1S1F1F1F100.240 V) 
E) (F1F1F1S1F1F1F100.480 V) 
A) (F1F1F1S1F1F1F100.080 V) 
B) (F1F1F1S1F1F1F100.080 V) 
C) (F1F1F1S1F1F1F100.240 V) 
D) (F1F1F1S1F1F1F100.240 V) 
E) (F1F1F1S1F1F1F100.480 V)

Question 6

Use the table of standard reduction potentials below to identify the metal or metal ion that is the strongest reducing agent. Standard Reduction
Potentials (volts) in Aqueous Solution   F1F1F1S1F1F1F101.80   F1F1F1S1F1F1F101.50   F1F1F1S1F1F1F100.771   F1F1F1S1F1F1F100.535   F1F1F1S1F1F1F100.124   F1F1F1S1F1F1F101.66   F1F1F1S1F1F1F102.37   F1F1F1S1F1F1F102.93

Accepted Answer

A) Pb4F1F1F1S1F1F1F10 
B) Pb2F1F1F1S1F1F1F10 
C) KF1F1F1S1F1F1F10 
D) K 
E) Al 
A) Pb4F1F1F1S1F1F1F10 
B) Pb2F1F1F1S1F1F1F10 
C) KF1F1F1S1F1F1F10 
D) K 
E) Al

Question 7

The capacity of a battery usually is specified as some number of ampere-hours (A F1F1F1S1F1F1F10 hr). This number is a measure of the ________ that the battery can supply.

Accepted Answer

A) energy 
B) power 
C) current 
D) number of electrons 
E) lifetime 
A) energy 
B) power 
C) current 
D) number of electrons 
E) lifetime

Question 8

Oxidation refers to ________

Accepted Answer

A) an increase in oxidation number. 
B) a decrease in oxidation number. 
C) a gain in the number of protons. 
D) an increase in the atomic number. 
E) an increase in mass. 
A) an increase in oxidation number. 
B) a decrease in oxidation number. 
C) a gain in the number of protons. 
D) an increase in the atomic number. 
E) an increase in mass.

Question 9

The oxidation of hydrogen by oxygen is one of the most-used reactions in fuel-cell technology. The overall reaction, which is given below, has a F1F1F1S1F1F1F10GF1F1F1S1F1F1F10 value of F1F1F1S1F1F1F10237 kJ/mol. What is the standard cell potential for this fuel cell?

Accepted Answer

A) 2.46 V 
B) 4.91 V 
C) 1.23 V 
D) 3.05 V 
E) 1.50 V 
A) 2.46 V 
B) 4.91 V 
C) 1.23 V 
D) 3.05 V 
E) 1.50 V

Question 10

How long would it take to electroplate a flute with 28.3 g of silver at a constant current of 2.0 amps using AgNO3?

Accepted Answer

A) 211 min 
B) 422 min 
C) 844 min 
D) 1,688 min 
E) 105 min 
A) 211 min 
B) 422 min 
C) 844 min 
D) 1,688 min 
E) 105 min

Question 11

The numerical value of the Faraday constant is approximately 96,500. This value represents ________

Accepted Answer

A) the coulombs of charge carried by one mole of electrons. 
B) the number of electrons required to produce a charge of one coulomb. 
C) the number of electrons required to produce one mole of electrical charge. 
D) the number of ions produced by removing one mole of electrons. 
E) the electrical current produced by transferring one mole of electrons. 
A) the coulombs of charge carried by one mole of electrons. 
B) the number of electrons required to produce a charge of one coulomb. 
C) the number of electrons required to produce one mole of electrical charge. 
D) the number of ions produced by removing one mole of electrons. 
E) the electrical current produced by transferring one mole of electrons.

Question 12

This is a true story; can you explain what happened? Prior to a really important dinner party, the hostess discovered that her silverware was very tarnished. She needed a quick fix. She remembered reading that the tarnish (Ag2S) would be removed if you immersed the silverware in a hot solution of baking soda (NaHCO3) in a pan lined with aluminum foil. So she did, and so it was, but she noticed a bit of a rotten egg smell (H2S) being produced. Metal/Metal ion   silver/silver(I)
0)799
Aluminum/aluminum(III)F1F1F1S1F1F1F101.677

Accepted Answer

A) Aluminum ions react with S2F1F1F1S1F1F1F10, form an aluminum sulfide precipitate, and gaseous carbon dioxide is released. 
B) Silver ions in the presence of the baking soda, (NaHCO3), oxidize the sulfide to elemental sulfur that attacks the aluminum foil, which produces the smelly aluminum sulfide. 
C) The aluminum acts as a reducing agent for the silver(I) in the silver sulfide; then the bicarbonate ion protonates the sulfide ion that is released. 
D) Aluminum is plated onto the silver surface, making it shiny again, and then the reaction of the bicarbonate with the aluminum oxide releases CO2. 
E) Silver in Ag2S reduces the aluminum, becomes metallic silver in the process, and releases hydrogen sulfide, H2S. 
A) Aluminum ions react with S2F1F1F1S1F1F1F10, form an aluminum sulfide precipitate, and gaseous carbon dioxide is released. 
B) Silver ions in the presence of the baking soda, (NaHCO3), oxidize the sulfide to elemental sulfur that attacks the aluminum foil, which produces the smelly aluminum sulfide. 
C) The aluminum acts as a reducing agent for the silver(I) in the silver sulfide; then the bicarbonate ion protonates the sulfide ion that is released. 
D) Aluminum is plated onto the silver surface, making it shiny again, and then the reaction of the bicarbonate with the aluminum oxide releases CO2. 
E) Silver in Ag2S reduces the aluminum, becomes metallic silver in the process, and releases hydrogen sulfide, H2S.

Question 13

The average electrical current delivered if 1.0 g of zinc were oxidized to zinc(II) in 60 s is ________

Accepted Answer

A) 29.5 A. 
B) 49.2 A. 
C) 24.6 A. 
D) 3.05 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F102 A. 
E) 1.53 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F102 A. 
A) 29.5 A. 
B) 49.2 A. 
C) 24.6 A. 
D) 3.05 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F102 A. 
E) 1.53 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F102 A.

Question 14

What is the change in free energy for a 1.50 V alkaline battery in which 2 moles of electrons are transferred from the anode to the cathode?

Accepted Answer

F1F1F1S1F

Question 15

An electrochemical cell is represented below. Which statement about this cell is not correct? Cu(s)|Cu2F1F1F1S1F1F1F10(aq) (0.20 M )||AgF1F1F1S1F1F1F10(aq) (0.10 M )|Ag(s)

Accepted Answer

A) Copper is oxidized. 
B) Silver ion is reduced. 
C) Two moles of electrons are transferred in the balanced reaction equation. 
D) Electrons flow from the copper to the silver electrode. 
E) The cell potential is determined by the standard half-cell potentials alone. 
A) Copper is oxidized. 
B) Silver ion is reduced. 
C) Two moles of electrons are transferred in the balanced reaction equation. 
D) Electrons flow from the copper to the silver electrode. 
E) The cell potential is determined by the standard half-cell potentials alone.

Question 16

Which statement regarding voltaic cells is not correct?

Accepted Answer

A) Reduction occurs at the cathode. 
B) Anions move through the barrier or bridge toward the electrode where oxidation is occurring. 
C) The electrode where reduction is occurring is represented by a positive sign. 
D) Electrons flow in the external circuit from the cathode to the anode. 
E) Electrons flow in the external circuit toward the electrode represented by a positive sign. 
A) Reduction occurs at the cathode. 
B) Anions move through the barrier or bridge toward the electrode where oxidation is occurring. 
C) The electrode where reduction is occurring is represented by a positive sign. 
D) Electrons flow in the external circuit from the cathode to the anode. 
E) Electrons flow in the external circuit toward the electrode represented by a positive sign.

Question 17

The following reaction occurs in a new battery called the super iron battery. In this reaction, ________ is reduced.

Accepted Answer

A) Fe in K2FeO4 
B) Zn metal 
C) Fe in Fe2O3 
D) Zn in ZnO 
E) Zn in K2ZnO2 
A) Fe in K2FeO4 
B) Zn metal 
C) Fe in Fe2O3 
D) Zn in ZnO 
E) Zn in K2ZnO2

Question 18

Reduction refers to ________

Accepted Answer

A) a decrease in oxidation number. 
B) an increase in oxidation number. 
C) a gain in the number of protons. 
D) a decrease in the atomic number. 
E) loss of mass. 
A) a decrease in oxidation number. 
B) an increase in oxidation number. 
C) a gain in the number of protons. 
D) a decrease in the atomic number. 
E) loss of mass.

Question 19

An electrochemical cell is constructed with a zinc metal anode in contact with a 0.052 M solution of zinc(II) nitrate and a silver cathode in contact with a 0.0042 M solution of silver(I) nitrate. What is the emf of this cell at 5F1F1F1S1F1F1F10C? Metal/Metal ion   silver/silver(I)F1F1F1S1F1F1F100.799 V
Zinc/zinc(II)F1F1F1S1F1F1F100.762 V

Accepted Answer

A) 1.656 V 
B) 1.465 V 
C) 1.561 V 
D) 1.370 V 
E) 1.609 V 
A) 1.656 V 
B) 1.465 V 
C) 1.561 V 
D) 1.370 V 
E) 1.609 V

Question 20

Consider an electrochemical cell with a Zn electrode in ZnSO4(aq) and a Cu electrode in CuSO4(aq). The overall chemical reaction is   Which one of the following statements is correct?

Accepted Answer

A) Copper is oxidized at the anode. 
B) One mole of electrons is transferred in this reaction. 
C) Zinc is reduced at the cathode. 
D) Copper ions are reduced at the cathode. 
E) Electrons travel from the Cu electrode to the Zn electrode. 
A) Copper is oxidized at the anode. 
B) One mole of electrons is transferred in this reaction. 
C) Zinc is reduced at the cathode. 
D) Copper ions are reduced at the cathode. 
E) Electrons travel from the Cu electrode to the Zn electrode.

Which of the following is not an advantage in using hydrogen fuel cells rather than gasoline engines in vehicles?

A NiMH battery uses ________ as the reducing agent.

A typical AA battery has a capacity of 0.500 ampere-hours (A  hr). How many electrons can such a battery supply?

If the free-energy change of the following voltaic cell is 46.3 kJ, what is the standard potential of the cell?

Use the table of standard reduction potentials below to identify the metal or metal ion that is the strongest reducing agent. Standard Reduction Potentials (volts) in Aqueous Solution 1.80 1.50 0.771 0.535 0.124 1.66 2.37 2.93

The capacity of a battery usually is specified as some number of ampere-hours (A  hr). This number is a measure of the ________ that the battery can supply.

Oxidation refers to ________

The oxidation of hydrogen by oxygen is one of the most-used reactions in fuel-cell technology. The overall reaction, which is given below, has a G value of 237 kJ/mol. What is the standard cell potential for this fuel cell?

How long would it take to electroplate a flute with 28.3 g of silver at a constant current of 2.0 amps using AgNO₃?

The numerical value of the Faraday constant is approximately 96,500. This value represents ________

The average electrical current delivered if 1.0 g of zinc were oxidized to zinc(II) in 60 s is ________

What is the change in free energy for a 1.50 V alkaline battery in which 2 moles of electrons are transferred from the anode to the cathode?

An electrochemical cell is represented below. Which statement about this cell is not correct? Cu(s)|Cu²^(aq) (0.20 M )||Ag^(aq) (0.10 M )|Ag(s)

Which statement regarding voltaic cells is not correct?

The following reaction occurs in a new battery called the super iron battery. In this reaction, ________ is reduced.

Reduction refers to ________

Consider an electrochemical cell with a Zn electrode in ZnSO₄(aq) and a Cu electrode in CuSO₄(aq). The overall chemical reaction is Which one of the following statements is correct?

Matter and Energy: The Origin of the Universe

Atoms, Ions, and Molecules: Matter Starts Here

Stoichiometry: Mass, Formulas, and Reactions

Solution Chemistry: The Hydrosphere

Thermochemistry: Energy Changes in Reactions

Properties of Gases: The Air We Breathe

A Quantum Model of Atoms: Waves and Particles

Chemical Bonds: What Makes a Gas a Greenhouse Gas

Molecular Geometry: Shape Determines Function

Intermolecular Forces: The Uniqueness of Water

Solutions: Properties and Behavior

Solids: Crystals, Alloys, and Polymers

Chemical Kinetics: Reactions in the Atmosphere

Chemical Equilibrium: How Much Product Does a Reaction Really Make

Acidbase Equilibria: Proton Transfer in Biological Systems

Additional Aqueous Equilibria: Chemistry and the Oceans

Thermodynamics: Spontaneous and Nonspontaneous Reactions and Processes

Nuclear Chemistry: Applications to Energy and Medicine

Organic and Biological Molecules: the Compounds of Life

The Main Group Elements: Life and the Periodic Table

Transition Metals: Biological and Medical Applications

Filters

Exam 18: Electrochemistry: The Quest for Clean Energy

Which of the following is not an advantage in using hydrogen fuel cells rather than gasoline engines in vehicles?

A NiMH battery uses ________ as the reducing agent.

A typical AA battery has a capacity of 0.500 ampere-hours (A  hr). How many electrons can such a battery supply?

If the free-energy change of the following voltaic cell is 46.3 kJ, what is the standard potential of the cell?

Use the table of standard reduction potentials below to identify the metal or metal ion that is the strongest reducing agent. Standard Reduction Potentials (volts) in Aqueous Solution 1.80 1.50 0.771 0.535 0.124 1.66 2.37 2.93

The capacity of a battery usually is specified as some number of ampere-hours (A  hr). This number is a measure of the ________ that the battery can supply.

Oxidation refers to ________

The oxidation of hydrogen by oxygen is one of the most-used reactions in fuel-cell technology. The overall reaction, which is given below, has a G value of 237 kJ/mol. What is the standard cell potential for this fuel cell?

How long would it take to electroplate a flute with 28.3 g of silver at a constant current of 2.0 amps using AgNO3?

The numerical value of the Faraday constant is approximately 96,500. This value represents ________

The average electrical current delivered if 1.0 g of zinc were oxidized to zinc(II) in 60 s is ________

What is the change in free energy for a 1.50 V alkaline battery in which 2 moles of electrons are transferred from the anode to the cathode?

An electrochemical cell is represented below. Which statement about this cell is not correct? Cu(s)|Cu2(aq) (0.20 M )||Ag(aq) (0.10 M )|Ag(s)

Which statement regarding voltaic cells is not correct?

The following reaction occurs in a new battery called the super iron battery. In this reaction, ________ is reduced.

Reduction refers to ________

Consider an electrochemical cell with a Zn electrode in ZnSO4(aq) and a Cu electrode in CuSO4(aq). The overall chemical reaction is Which one of the following statements is correct?

Matter and Energy: The Origin of the Universe

Atoms, Ions, and Molecules: Matter Starts Here

Stoichiometry: Mass, Formulas, and Reactions

Solution Chemistry: The Hydrosphere

Thermochemistry: Energy Changes in Reactions

Properties of Gases: The Air We Breathe

A Quantum Model of Atoms: Waves and Particles

Chemical Bonds: What Makes a Gas a Greenhouse Gas

Molecular Geometry: Shape Determines Function

Intermolecular Forces: The Uniqueness of Water

Solutions: Properties and Behavior

Solids: Crystals, Alloys, and Polymers

Chemical Kinetics: Reactions in the Atmosphere

Chemical Equilibrium: How Much Product Does a Reaction Really Make

Acidbase Equilibria: Proton Transfer in Biological Systems

Additional Aqueous Equilibria: Chemistry and the Oceans

Thermodynamics: Spontaneous and Nonspontaneous Reactions and Processes

Nuclear Chemistry: Applications to Energy and Medicine

Organic and Biological Molecules: the Compounds of Life

The Main Group Elements: Life and the Periodic Table

Transition Metals: Biological and Medical Applications

Filters

How long would it take to electroplate a flute with 28.3 g of silver at a constant current of 2.0 amps using AgNO₃?

An electrochemical cell is represented below. Which statement about this cell is not correct? Cu(s)|Cu²^(aq) (0.20 M )||Ag^(aq) (0.10 M )|Ag(s)

Consider an electrochemical cell with a Zn electrode in ZnSO₄(aq) and a Cu electrode in CuSO₄(aq). The overall chemical reaction is Which one of the following statements is correct?