When a lead storage battery is charged:

Consider the figure and answer the following questions.
$(i)$ Cell $'A'$ has $E_{cell} = 2 \ V$ and cell $'B'$ has $E_{cell} = 1.1 \ V$. Which of the two cells,$'A'$ or $'B'$,will act as an electrolytic cell? Which electrode reactions will occur in this cell?
$(ii)$ If cell $'A'$ has $E_{cell} = 0.5 \ V$ and cell $'B'$ has $E_{cell} = 1.1 \ V$,then what will be the reaction at the anode and cathode?

Which of the following metals will not react with a solution of $CuSO_4$?

On the basis of the information available from the reaction $\frac{4}{3} Al + O_2 \to \frac{2}{3} Al_2O_3$,$\Delta G = -827 \ kJ \ mol^{-1}$ of $O_2$,the minimum emf required to carry out an electrolysis of $Al_2O_3$ is $............... \ V$

For a $Ag-Zn$ button cell,the net reaction is $Zn_{(s)} + Ag_{2}O_{(s)} \rightarrow ZnO_{(s)} + 2Ag_{(s)}$. Given $\Delta G_{f}^{o}(Ag_{2}O) = -11.21 \ kJ \ mol^{-1}$ and $\Delta G_{f}^{o}(ZnO) = -318.3 \ kJ \ mol^{-1}$,the $E^{o}_{cell}$ of the button cell is ......... $V$.

The reference electrode is made by using