The e.m.f. of a cell whose half cells are given below is .............. $V$
$Mg^{2+} + 2e^- \to Mg_{(s)}$; $E^o = - 2.37 \ V$
$Cu^{2+} + 2e^- \to Cu_{(s)}$; $E^o = + 0.34 \ V$

The standard electrode potentials $\left( E_{M^{+}/M}^\circ \right)$ of four metals $A, B, C$ and $D$ are $-1.2 \ V, 0.6 \ V, 0.85 \ V$ and $-0.76 \ V$,respectively. The sequence of deposition of metals on applying potential is

Arrange the following metals in the order of their decreasing standard electrode potential: $Mg, K, Ba, Ca$.

Which method can be used to determine the strength of a reductant or oxidant in a solution? Explain with an example.

$E^o_{cell}$ for the cell: $Pt_{(s)} | H_{2(g)} | HCOOH_{(aq)} || CH_3COOH_{(aq)} | H_{2(g)} | Pt_{(s)}$ at $25^oC$ is ............ $V$. ($K_a$ of $HCOOH = 2.4 \times 10^{-4}$,$K_a$ of $CH_3COOH = 1.8 \times 10^{-5}$,$\log 2 = 0.3$,$\log 3 = 0.477$,$\frac{2.303RT}{F} = 0.059$ or $0.06$)

Given the standard half-cell potentials $(E^{\circ})$ as: $Zn \rightarrow Zn^{2+} + 2e^{-}$; $E^{\circ} = +0.76 \ V$ and $Fe \rightarrow Fe^{2+} + 2e^{-}$; $E^{\circ} = +0.41 \ V$. Then the standard e.m.f. of the cell with the reaction $Fe^{2+} + Zn \rightarrow Zn^{2+} + Fe$ is: