Write the reactions for the following processes:
$A$. Electrolysis of water at the anode and cathode.
$B$. Electrolytic reaction of molten $NaCl$.

When $CuSO_4$ is electrolyzed using platinum electrodes,what happens?

Which is the simplest electrolytic cell? Give a detailed note on it.

If electrolysis of aqueous $CuSO_4$ solution is carried out using $Cu$ electrodes, the reaction taking place at the anode is:

What is electrolysis? What can be produced with the help of electrolysis?

Given below are two statements $:$
$1 \ M$ aqueous solution of each of $Cu(NO_3)_2, AgNO_3, Hg_2(NO_3)_2$ and $Mg(NO_3)_2$ are electrolysed using inert electrodes.
Given $: E_{Ag^{+}/Ag}^{\theta} = 0.80 \ V, E_{Hg_2^{2+}/Hg}^{\theta} = 0.79 \ V, E_{Cu^{2+}/Cu}^{\theta} = 0.24 \ V$ and $E_{Mg^{2+}/Mg}^{\theta} = -2.37 \ V$.
Statement $(I) :$ With increasing voltage,the sequence of deposition of metals on the cathode will be $Ag, Hg$ and $Cu$.
Statement $(II) :$ Magnesium will not be deposited at cathode instead oxygen gas will be evolved at the cathode.
In the light of the above statement,choose the most appropriate answer from the options given below.