The electroplating of $Cr$ is undertaken because:

What happens to the $pH$ during the electrolysis of aqueous $CuSO_4$ using platinum electrodes?

Which of the following is a property of a solution of dry hydrogen chloride in dry methylbenzene?

$O_2$ gas will be evolved as a product of electrolysis of $:$
$(A)$ an aqueous solution of $AgNO_3$ using silver electrodes.
$(B)$ an aqueous solution of $AgNO_3$ using platinum electrodes.
$(C)$ a dilute solution of $H_2 SO_4$ using platinum electrodes.
$(D)$ a high concentration solution of $H_2 SO_4$ using platinum electrodes.
Choose the correct answer from the options given below $:$

Assertion : $A$ small amount of acid or alkali is added before electrolysis of water.
Reason : Pure water is a weak electrolyte.

Electrolysis of $KCl \cdot MgCl_2 \cdot 6H_2O$ gives