Chapter 19.6, Problem 1PPB

Interpretation Introduction

Interpretation:

The partial pressure of ${\text{H}}_2$ necessary in anode compartment is to be determined with cell potential, standard cell potential, pH of anode compartment, concentration of chlorine ion in cathode compartment, and temperature.

Concept introduction:

The function of concentrations of those chemical species that are involved in a chemical reaction is known as the reaction quotient and is represented as $Q$.

The Nernst equation which is used to determine the cell potential is as follows: $E\text{ = }{E}^{°}-\frac{\text{R}T}{n\text{F}}\log Q$

Here, $E$ is the cell potential, $E^{°}$ is the standard cell potential, $Q$ is the reaction quotient, $n$ is the transfer of electrons in the half-cell reactions, $\text{F}$ is Faraday’s constant $\left(96500\text{ J/V}\text{.mol}\right)$, and $\text{R}$ is universal constant $\left(8.314\text{ J/K}\text{.mol}\right)$.

The reaction quotient is the ratio of molar concentration of the ions in the product to that of reactants, raised to power their stoichiometric coefficient.

$Q=\frac{\text{concentration}\text{of}\text{product}}{\text{concentration}\text{of}\text{reactant}}$

The relationship between temperature units, Kelvin and Celsius, can be expressed as: $\text{K}{=}^{\circ }\text{C}+273$

The pH of a compound is calculated by the expression: $\begin{array}{c}\text{pH}=-\text{log}\left[{\text{H}}^{+}\right]\\ \left[{\text{H}}^{+}\right]={10}^{-\text{pH}}\end{array}$