Which metal cannot be obtained by the electrolysis of its aqueous salt solution?

Predict the products of electrolysis in each of the following:
$(i)$ An aqueous solution of $AgNO_3$ with silver electrodes.
$(ii)$ An aqueous solution of $AgNO_3$ with platinum electrodes.
$(iii)$ $A$ dilute solution of $H_2SO_4$ with platinum electrodes.
$(iv)$ An aqueous solution of $CuCl_2$ with platinum electrodes.

The incorrect statement about the Castner-Kellner cell process is

If $0.50 \ L$ of a $0.60 \ M$ $SnSO_4$ solution is electrolyzed for a period of $30.0 \ min$ using a current of $4.60 \ A$ with inert electrodes,what is the final concentration of $Sn^{2+}$ remaining in the solution? (Atomic weight of $Sn = 119$)

Which of the following is not a conductor of electricity?

For gold plating,the electrolyte used is