A current of 12 ampere is passed through an electrolytic cell containing aq. `NiSO_(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 ?
(At.mass of Ni = 98.7)

Options

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

Answer

C

Explanation

`Q = I xx t (s) 12 xx 60 xx 60 = 43200` C .
`Ni^(2+) + 2e^(-) to Ni` .
Theortically , `2 xx 96500` C will deposit Ni = 58.7 g . Hence , 43200 C will deposit Ni = 13.137 g .
As current efficiency is 60 % , mass actually deposited = `(60)/(100) xx 13.137` = 7.88 g .