Electrochemistry Review

Front

What is the relationship between E° and ΔG° in a galvanic cell?

Back

ΔG° = -nFE°, where ΔG° is the change in Gibbs free energy, n is the number of moles of electrons transferred, F is Faraday's constant, and E° is the standard cell potential.

Front

What happens to the voltage in a galvanic cell when a more concentrated solution of a reactant is added?

Back

The voltage increases due to the increased concentration of reactants, which shifts the equilibrium position according to Le Chatelier's principle.

Front

Identify the species that is oxidized in a redox reaction.

Back

The species that loses electrons is oxidized. For example, in the reaction between Al and Zn, Al is oxidized to Al³⁺.

Front

What does the formation of a reddish solid on zinc wire in CuSO₄ solution indicate?

Back

It indicates that Cu²⁺ ions are being reduced to solid Cu, and the standard reduction potential for Cu²⁺ is greater than that of Zn²⁺.

Front

How do you calculate the current required to produce a certain amount of substance in electrolysis?

Back

Use the formula: I = (nF)/t, where I is the current in amperes, n is the number of moles of substance, F is Faraday's constant, and t is time in seconds.

Front

What is Faraday's constant?

Back

Faraday's constant (F) is approximately 96485 C/mol, representing the charge of one mole of electrons.

Front

Define standard reduction potential (E°).

Back

Standard reduction potential is the measure of the tendency of a chemical species to be reduced, measured under standard conditions.

Front

What is the significance of a positive E° value?

Back

A positive E° value indicates that the reduction reaction is spontaneous under standard conditions.

Front

What is oxidation in terms of electron transfer?

Back

Oxidation is the process of losing electrons, resulting in an increase in oxidation state.

Front

What is reduction in terms of electron transfer?

Back

Reduction is the process of gaining electrons, resulting in a decrease in oxidation state.