Question

Find out the volume of gases evolved by passing $0.965A$ current for $1hr$ through an aqueous solution of ${CH}_{3}COONa$ at ${25}^{o}C$ and $1atm$

Answer 1

The reaction evolving gas is :

Cathode :

$2H_{2}O+e^{-}\to {OH}^{(-)}+H^0$

$2H^0\to H_2$

i.e. $2H_{2}O+2e^{-}\to 2{OH}^{(-)}+H_2$

mol. of Faraday $=\frac{Q}{F}=\frac{I\times t}{F}$

$=\frac{0.965\times 60\times 60}{96500}$

$=0.036mol.$

2 mol. F gives 1 mol $H_2$

0.036 mol $\to \frac{1}{2}\times 0.036$

$=0.018$ mol of $H_2$

$\therefore$ Volume $=22.4\times 0.018$

$=0.4032L$

$=403.2$ ml. of $H_2$