Question

The mass of copper that will be deposited at cathode in electrolysis of $0.2M$ solution of copper sulphate when a quantity of electricity equal to hat required to liberate $2.24L$ of hydrogen from $0.1M$ aqueous $H_{2}S{O}_4$ is passed (atomic mass of $C=63.5$) will be:

• A. $1.59g$
• B. $3.18g$
• C. $6.35g$
• D. $12.70g$

Answer 1

The correct option is C $6.35g$

$1F=1Eq$ of $H_2$ = $11.2L$ of $H_2$

$11.2L$ of $H_2$ = $1Eq$ of $H_2$

$2.24L$ of $H_2=\frac{2.24}{11.2}=0.2Eq$

$\therefore$ $0.2Eq$ of $Cu$ will be deposited.

$1Eq$ of $Cu$ = $\frac{63.5}{2}g$

$0.2Eq$ of $Cu$ = $\frac{63.5}{2}\times 0.2$ = $6.35g$