If $E^0_{Fe^{3+}/Fe} = x \ V$ and $E^0_{Fe^{2+}/Fe} = y \ V$,then what will be the value of $E^0_{Fe^{3+}/Fe^{2+}}$?

For the cell reaction,$2Ce^{4+} + Co \to 2Ce^{3+} + Co^{2+}$,$E^\circ_{cell}$ is $1.89 \ V$. If $E^\circ_{Co^{2+}/Co} = -0.28 \ V$,then $E^\circ_{Ce^{4+}/Ce^{3+}}$ is equal to:

Which one of the following metals cannot evolve $H_2$ from acids,$H_2O$,or from its compounds?

Calculate the standard cell potential for a cell having the following reaction: $2 Al_{(s)} + 3 Ni^{2+} \rightarrow 2 Al^{3+} + 3 Ni_{(s)}$ given that $E_{Ni^{2+}/Ni}^{\circ} = -0.25 \ V$ and $E_{Al^{3+}/Al}^{\circ} = -1.66 \ V$. (in $V$)

Given electrode potentials:
$Fe^{3+} + e^- \to Fe^{2+}$; $E^o = 0.771 \, V$
$I_2 + 2e^- \to 2I^-$; $E^o = 0.536 \, V$
$E^o_{\text{cell}}$ for the cell reaction
$2Fe^{3+} + 2I^- \to 2Fe^{2+} + I_2$ is:

Arrange the following metals in the order in which they displace each other from the solution of their salts: $Al, Cu, Fe, Mg$ and $Zn$.