Question

A current of $3.7$ ampere is passed for $6$ hrs. between Ni electrodes in $0.5$ litre of $2$M solution of $Ni(N{O}_3{)}_2$. What will be the molarity of solution at the end of electrolysis?

Answer 1

The electrolysis of $Ni(N{O}_3{)}_2$ in presence of $Ni$ electrode will bring in following changes :

At anode : $Ni\to N{i}^{2+}+2e$

At cathode : $N{i}^{2+}+2e\to Ni$

Eq. of $N{i}^{2+}$ formed = Eq. of $N{i}^{2+}$ lost

Thus , there will be no change in conc. of $Ni(N{O}_3{)}_2$ solution during electrolysis i.e.,

It will remain $2M$