Four alkali metals $A$,$B$,$C$ and $D$ have standard electrode potentials of $-3.05 \ V$,$-1.66 \ V$,$-0.40 \ V$ and $0.80 \ V$ respectively. Which one will be the most reactive?

What will be the $EMF$ of the cell formed by the following half-cells in $V$?
$Mg^{2+} + 2e^- \to Mg_{(s)}; E = -2.37 \ V$
$Cu^{2+} + 2e^- \to Cu_{(s)}; E = +0.33 \ V$

Which of the following reactions will be spontaneous in an electrochemical cell constructed from the given standard electrode potentials: $E_{Cl_2 \mid 2Cl^-}^0 = 1.36 \ V$ and $E_{Br_2 \mid 2Br^-}^0 = 1.09 \ V$?

The standard reduction potentials at $25^o \text{C}$ for $Li^{+}/Li$,$Ba^{2+}/Ba$,$Na^{+}/Na$,and $Mg^{2+}/Mg$ are $-3.05 \ V$,$-2.73 \ V$,$-2.71 \ V$,and $-2.37 \ V$ respectively. Which of the following is the strongest oxidizing agent?

$(i)$ Copper metal dissolves in $1 \ M$ silver nitrate solution and crystals of silver metal get deposited.
$(ii)$ Silver metal does not react with $1 \ M$ zinc nitrate solution.
$(iii)$ Zinc metal dissolves in $1 \ M$ copper sulphate solution and copper metal gets deposited.
Hence,the order of decreasing strength of the three metals as reducing agents will be:

Standard electrode potential of $Ag^{+}/Ag$ and $Cu^{2+}/Cu$ is $+0.80 \ V$ and $+0.34 \ V$ respectively. These electrodes are joined together by a salt bridge. If: