Question

A current of $12$ ampere is passed through an electrolytic cell containing aqueous $NiS{O}_4$ solution. Both $Ni$ and $H_2$ gas are formed at the cathode. The current efficiency is $60\%$. What is the mass of nickel deposited on the cathode per hour?

• A. $7.883g$
• B. $3.941g$
• C. $5.91g$
• D. $2.645g$

Answer 1

Answer: (A)

$N{i}^{-}+2e^{-}\to Ni$ (at cathode)
Equivalent weight of $Ni=\frac{\text{ mol.wt }}{\text{ gain electron }}$
$=\frac{58.7}{2}$
$=29.35$
$i=12A,t=1h$
$=60\times 60s,Z$
$=\frac{Equ.wt.}{96500}$
Weight of deposite $Ni=\frac{\text{ Zit }\times \text{ efficiency }}{100}$
$=\frac{29.35\times 12\times 60\times 60\times 60}{96500\times 100}$
$=7.883g$