Chapter 18, Problem 18.131QP

Interpretation Introduction

Interpretation:

A method to obtain cell potential from a concentration cell when concentrations of the species in both the half cells are same has to be explained.

Concept Introduction:

Concentration cell is an electrochemical cell in which the two half cells are the same. The potential produced in the concentration cell is due to the different concentrations of the reacting species.  The cell potential of a concentration cell can be found by Nernst equation.

${\text{E}}_{\text{cell}}{\text{=E}}^{\text{°}}{}_{\text{cell}}\text{-}\frac{\text{RT}}{\text{2}\text{.303nF}}\text{log}\frac{\left[\text{dilute species}\right]}{\left[\text{concentrated species}\right]}$

Where,

${\text{E}}_{\text{cell}}$ is the potential of the cell at a given temperature

${\text{E}}^{\text{°}}{}_{\text{cell}}$ is the standard electrode potential

$\text{R}$ is the universal gas constant $\text{(R=8}{\text{.314JK}}^{\text{-1}}{\text{mol}}^{\text{-1}})$

$\text{T}$ is the temperature

$\text{n}$ is the number of electrons involved in a reaction

$\text{F}$ is the Faraday constant $\text{(F=9}\text{.64853399}\times {\text{10}}^4{\text{Cmol}}^{\text{-1}})$