CHEM122 Electrochemistry

What is electrochemistry?

The study of the interchange of chemical and electrical energy, primarily through oxidation-reduction reactions.

What does cell potential indicate?

It indicates the voltage produced by a galvanic cell, representing the driving force behind the electrochemical reaction.

Define Gibbs Free Energy (ΔG).

A thermodynamic potential that measures the maximum reversible work obtainable from a thermodynamic system at constant temperature and pressure.

What is the process of oxidation?

Oxidation is the loss of electrons during a redox reaction.

What occurs at the anode in a galvanic cell?

Oxidation occurs at the anode.

What is a salt bridge's function in a galvanic cell?

It maintains electrical neutrality by allowing the flow of ions between the half-cells.

How is standard reduction potential (E°) defined?

It measures the tendency of a species to be reduced, with the standard hydrogen electrode set at 0.0 V.

What is the relationship between Gibbs Free Energy and cell potential?

ΔG° = -nFE°cell, indicating that a negative ΔG° corresponds to a positive E°cell.

What does the Nernst equation describe?

It relates cell potential to the concentrations of reactants and products under non-standard conditions.

How does increasing reactant concentration affect cell potential?

Increasing the concentration of reactants generally increases the cell potential.

What is electrolysis?

A process that uses electrical energy to drive non-spontaneous chemical reactions.

What is the reaction in a lead storage battery?

Pb + PbO2 + 2H+ + 2HSO4– → 2PbSO4 + 2H2O, converting chemical energy to electrical energy.

How does cathodic protection prevent corrosion?

By attaching a more reactive metal to the metal needing protection, sacrificing itself instead of the protected metal.

What is a concentration cell?

A type of galvanic cell made of two half-cells with different concentrations of the same ion.

What is one practical application of electrolysis?

Electroplating, where metals are deposited onto surfaces like silver or copper.

What is the Faraday constant (F)?

F is the amount of electric charge per mole of electrons, approximately 96485 C/mol.

What is reduction in electrochemistry?

Reduction is the gain of electrons during a redox reaction.

What happens at the cathode of a galvanic cell?

Reduction occurs at the cathode.

Define an electrolyte.

An electrolyte is a substance that produces an ion in solution, allowing for electrical conductivity.

What is the role of a galvanic cell?

A galvanic cell converts chemical energy into electrical energy via spontaneous redox reactions.

Explain the term 'leakage current.'

Leakage current is the small amount of electric current that flows through an insulator.

What is an anode in electrochemistry?

The anode is the electrode where oxidation occurs.

What is the difference between a primary and secondary battery?

Primary batteries are non-rechargeable, while secondary batteries can be recharged and reused.

What is the significance of the mobility of ions in an electrolyte?

The mobility of ions affects the conduction of electricity and the efficiency of electrochemical processes.

What is the significance of the standard electrode potential?

The standard electrode potential indicates the likelihood of a species to be reduced, influencing reaction spontaneity.