Question

A current of 3.7 A is passed for six hours between $Ni$ electrode in 0.5 litre of $2M$ solution of $Ni(N{O}_3{)}_2$. The molarity of solution at the end of electrolysis is:

Answer 1

The electrolysis of $Ni(N{O}_3{)}_2$ using Ni electrode (i.e., Attacked electrodes) shows the following changes.
Anode : $Ni\to N{i}^{2+}+2e$
Cathode: $Ni\to N{i}^{2+}+2e$
The equivalent of $N{i}^{2+}$ formed = Equivalent of $N{i}^{2+}$ lost
Thus, no change in molarity of $Ni(N{O}_3{)}_2$ solution or it remains $2M$