Chapter 22, Problem 23E

Interpretation Introduction

(a)

Interpretation:

The value of $E^0$ for the below reaction needs to be determined.

${\text{I}}_{\text{2}}\left(\text{aq}\right)+{\text{I}}^{-}\left(\text{aq}\right)\rightleftarrows {\text{I}}_3{}^{-}\left(\text{aq}\right)$

Concept introduction:

The relation between Gibbs free energy and electrode potential is as follows: $\Delta G^0=-RT\ln K$

Here, $\Delta G^0$ is change in Gibbs free energy, R is Gas constant and K is equilibrium constant.

Interpretation Introduction

(b)

Interpretation:

The fraction of ${\text{I}}_{\text{2}}$ remains unreacted at equilibrium needs to be determined, if a sample $0.00\text{1}0\text{ mol}$

${\text{I}}_{\text{2}}$ is added to $\text{1}.0\text{ L of }0.00\text{5}0\text{ M NaI}(\text{aq)}$ at $25°\text{C}$.

Concept introduction:

The concentration is related to moles of solute and volume of solution as follows:

$\text{Concentration=}\frac{\text{Moles}\text{of}\text{solute}}{\text{Volume}\text{of}\text{solution}}$

For a general equilibrium reaction as follows:

$A+B\rightleftharpoons AB$

The equilibrium constant can be represented as follows:

$K=\frac{\left[AB\right]}{\left[A\right]\left[B\right]}$

Here, $\left[AB\right]$, $\left[A\right]$ and $\left[B\right]$ are equilibrium concentrations.