Chapter 19, Problem 19.163MP

Interpretation Introduction

(a)

Interpretation:

The balanced equation for the given reaction in basic solution should be written.

Concept introduction:

The half-reaction method can be used to balance the redox equation using the following steps.

- Atoms that are oxidized and which are reduced should be determined.

- The two unbalanced half-cell reactions are written.

- Then the elements in the reaction except oxygen and hydrogen should be balanced.

- Oxygen atoms are balanced by adding water molecules to the opposite side of the equation.

- Hydrogen atoms are balanced by adding ${\text{H}}^{+}$ ions to the opposite side of the equation. In a basic medium, ${\text{OH}}^{-}$ ions are added to neutralize ${\text{H}}^{+}$ ions in the final step.

- Charges are made equal by adding electrons to a more positive side.

- The two half-reactions are multiplied by a suitable factor to equal the electron count in both half-equations.

- Two balanced half-equations are added together and electrons and other common species are canceled.

Interpretation Introduction

(b)

Interpretation:

$\Delta G^0$ for the reaction obtained in part (a) should be calculated.

Concept introduction:

The standard Gibbs free energy change can be calculated as follows:

$\begin{array}{l}\Delta G^0=-nF{E}^0\\ \\ \Delta G^0=\text{ Standard Gibbs free energy}\\ \text{n = number of moles of electrons transferred}\\ \text{F = Faraday constant}\\ {\text{E}}^0=\text{ Standard cell potential}\end{array}$