The cell reaction of the galvanic cell $Cu_{(s)} | Cu^{2+}_{(aq)} || Hg^{2+}_{(aq)} | Hg_{(l)}$ is

If a strip of $Cu$ metal is placed in a solution of ferrous sulphate,what will happen?

The equilibrium constant for the reaction $Zn_{(s)} + Sn^{2+}_{(aq)} \rightleftharpoons Zn^{2+}_{(aq)} + Sn_{(s)}$ is $1 \times 10^{20}$ at $298 \ K$. The magnitude of standard electrode potential of $Sn/Sn^{2+}$ if $E_{Zn^{2+}/Zn}^0 = -0.76 \ V$ is $............ \times 10^{-2} \ V$. (Nearest integer)
Given : $\frac{2.303 \ RT}{F} = 0.059 \ V$

$A$ variable,opposite external potential $(E_{ext})$ is applied to the cell $Zn | Zn^{2+} (1 \ M) || Cu^{2+} (1 \ M) | Cu$ of potential $1.1 \ V$. When $E_{ext} < 1.1 \ V$ and $E_{ext} > 1.1 \ V$,respectively,electrons flow from:

Which of the following is $NOT$ a function of a salt bridge?

$Zn_{(s)} | Zn^{2+}_{(aq)} || Cu^{2+}_{(aq)} | Cu_{(s)}$ is