Holt Ch 20

Multiple Choice

When electrons are transferred directly from Zn atoms to Cu2+ ions in an aqueous CuSO4 solution, what is the observable effect on the temperature of the solution?

• The temperature decreases

• The temperature remains the same

• The temperature rises

• The solution evaporates

Open Ended

Explain how the overall reaction for a Zn/Cu electrochemical cell is determined from the half-cell reactions.

Open Ended

Why is the study of electrochemical cells significant in understanding chemical reactions and energy transformation?

Open Ended

Describe the redox reactions that occur at the anode and cathode in a zinc-carbon dry cell, including the chemical equations involved.

Multiple Choice

In an electrochemical cell, which electrode is the site of oxidation?

• Anode

• Cathode

• Salt bridge

• Electrolyte

Multiple Select

Which of the following statements about oxidation-reduction reactions and electrochemistry are correct?

• Oxidation-reduction reactions involve a transfer of electrons.

• Electrochemistry deals with electricity-related applications of redox reactions.

• All redox reactions release energy as heat only.

• Electron transfer can result in electrical energy if substances are separated.

Multiple Choice

What is the main purpose of a porous barrier or salt bridge in an electrochemical cell?

• To separate the oxidation and reduction half-reactions

• To conduct electricity between electrodes

• To increase the rate of electron transfer

• To prevent the mixing of electrolytes

Multiple Choice

Which of the following best describes the function of an electrode in an electrochemical cell?

• It is a conductor that establishes electrical contact with a nonmetallic part of a circuit

• It separates the oxidation and reduction half-reactions

• It acts as a porous barrier

• It absorbs energy as heat

Open Ended

Explain how the movement of electrons and ions maintains the flow of electric current in an electrochemical cell.

Multiple Select

Which of the following statements about electrochemical cells are correct?

• Both oxidation and reduction must occur in an electrochemical reaction.

• The anode is where oxidation occurs.

• The cathode is where reduction occurs.

• Only one half-cell is needed for an electrochemical cell.

Multiple Choice

What is the correct notation for representing a complete electrochemical cell?

• anode electrode|anode solution||cathode solution|cathode electrode

• cathode electrode|cathode solution||anode solution|anode electrode

• anode solution|anode electrode||cathode electrode|cathode solution

• cathode solution|cathode electrode||anode electrode|anode solution

Open Ended

Discuss the advantages and disadvantages of different types of batteries (alkaline, rechargeable, mercury) from a consumer point of view.

Multiple Choice

Which of the following best describes the primary function of a voltaic cell?

• To convert chemical energy into electrical energy using spontaneous redox reactions

• To store electrical energy for later use

• To convert electrical energy into chemical energy

• To prevent corrosion in metals

Multiple Select

Which of the following are types of dry cells mentioned as examples of voltaic cells?

• Zinc-carbon battery

• Alkaline battery

• Mercury battery

• Lead-acid battery

Open Ended

Explain how the movement of electrons and ions work together to allow a voltaic cell to function.

Multiple Choice

In the electrochemical cell diagram, which electrode is the site of oxidation?

• Anode

• Cathode

• Porous barrier

• Copper strip

Multiple Choice

Which component is present in an acidic dry cell but not in an alkaline dry cell?

• Carbon rod (cathode)

• Steel jacket

• Porous separator

• KOH electrolyte

Multiple Select

Which of the following are true about alkaline batteries based on the slides?

• They do not have a carbon rod cathode.

• The half-reaction at the anode involves Zn and OH⁻.

• They use a moist paste of NH4Cl as electrolyte.

• The reduction at the cathode is the same as in zinc-carbon dry cells.

Multiple Choice

In the fuel cell diagram, what is the function of the porous graphite electrodes?

• They allow the transfer of electrons between the external circuit and the electrolyte.

• They store hydrogen and oxygen gases.

• They act as the electrolyte solution.

• They separate the anode and cathode compartments.

Open Ended

Explain how the reactants and products are managed in a fuel cell and why this makes fuel cells efficient.

Open Ended

What questions do you still have about electrochemical cells or the transfer of energy in these systems?

Open Ended

How does the transfer of electrons from Zn atoms to Cu2+ ions in an aqueous CuSO4 solution demonstrate the conversion of chemical energy to heat?