Question

The time required for a current of $3amp$. to decompose electrolytically $18g$ of $H_{2}O$ is:

• A. $18hour$
• B. $36hour$
• C. $9hour$
• D. $18seconds$

Answer 1

The correct option is A $18hour$

$H_{2}O\to O_2+2e^{-}$
2 far a days of charge required for 1 mole
$ie:2\times 96500C$
$2\times 96500=3\times t$
$\frac{2\times 96500}{3}=t=2\times 32166.67=64333.34sec$
$=\frac{64333.34}{60\times 60}hours$
$=17.87hours$