$A$ solution of copper sulphate may be kept safely in the container made up of

The correct statement/s about a Galvanic cell is/are:
$(a)$ Current flows from cathode to anode
$(b)$ Anode is the positive terminal
$(c)$ If $E_{cell} < 0$,then it is a spontaneous reaction
$(d)$ Cathode is the positive terminal

Some statements about Leclanché cell are:
$(I)$ Anode is zinc metal
$(II)$ Cathode is graphite rod surrounded by powdered $MnO_2$ and carbon
$(III)$ Electrolyte is a moist paste of $ZnO$ and $KOH$
$(IV)$ Oxidation product is $ZnO$
The correct statements are:

Write the reactions for the following:
$1.$ Oxidation and reduction reactions of a lead storage cell.
$2.$ Cell reaction of a $Ni-Cd$ cell.
$3.$ Anode,cathode,and overall reaction of a mercury cell.

Calculate $\Delta G^{\circ}$ for the following cell reaction.
$Zn_{(s)} + Ag_2O_{(s)} + H_2O_{(l)} \longrightarrow Zn^{2+}_{(aq)} + 2Ag_{(s)} + 2OH^{-}_{(aq)}$
Given: $E^{\circ}_{Ag^{+}/Ag} = +0.80 \ V$ and $E^{\circ}_{Zn^{2+}/Zn} = -0.76 \ V$

Why is an external $emf$ of more than $2.2 \ V$ required for the extraction of $Cl_2$ from brine?