Chapter 19, Problem 102FP

Interpretation Introduction

(a)

Interpretation:

Equations for the cell reactions that occur in the voltaic cells (1) and (2) should be written.

Concept introduction:

In amalgam electrode, metal-amalgam is in contact with a solution containing its own ions. The activities of highly reactive metals like first row elements are difficult to measure in aqueous solutions. So their activity is reduced by diluting with mercury.

Interpretation Introduction

(b)

Interpretation:

The value of Δ_rG for the cell reactions written in part (a) should be determined.

Concept introduction:

From the electrode potential of the cell, the value of Δ_rG can be calculated as follows:

${\Delta }_{r}G=-zF{E}_{cell}$

Here, z is number of electrons transferred in a reaction, F is Faraday’s constant and $E_{cell}$ is electrode potential of the cell.

Interpretation Introduction

(c)

Interpretation:

The overall equation obtained by combining the equation of part (a) should be written. And Δ_rG⁰ for the overall reaction should be established.

Concept introduction:

For a combination of reaction.

${\Delta }_r{G}_{overall}={\displaystyle \sum n{\Delta }_{r}G}$

Where, n is the number of species and ${\Delta }_{r}G$ is the Gibbs free energy value for each species.

Interpretation Introduction

(d)

Interpretation:

The value of E⁰_celland E⁰_Na⁺_/Nafor the overall reaction should be determined.

Concept introduction:

From the electrode potential of the cell, the value of Δ_rG can be calculated as follows:

${\Delta }_{r}G=-zF{E}_{cell}$

Here, z is number of electrons transferred in a reaction, F is Faraday’s constant and $E_{cell}$ is electrode potential of the cell.