$Cu^{+} + e^- \to Cu$ ; $E^o = X_1 \ V$
$Cu^{2+} + 2e^- \to Cu$ ; $E^o = X_2 \ V$
Then for $Cu^{2+} + e^- \to Cu^{+}$ ; $E^o$ will be ?

$A$ gas $X$ at $1 \, atm$ is bubbled through a solution containing a mixture of $1 \, M \, Y^{-}$ and $1 \, M \, Z^{-}$ at $25 \, ^oC$. If the reduction potential of $Z > Y > X$,then

$A$ cell constructed by coupling a standard copper electrode and a standard magnesium electrode has an $emf$ of $2.7 \ V$. If the standard reduction potential of the copper electrode is $+0.34 \ V$,the standard reduction potential of the magnesium electrode is .............. $V$.

What is the decreasing order of deposition of metal on electrode if standard reduction potentials are given as: $Ag^{+} | Ag = 0.80 \ V$,$Cu^{2+} | Cu = 0.337 \ V$,$Sn^{2+} | Sn = -0.136 \ V$,$Cd^{2+} | Cd = -0.403 \ V$?

The standard reduction potentials at $25^o C$ are given below. Which is the strongest reducing agent?
$Zn^{2+}_{(aq)} + 2e^{-} \rightleftharpoons Zn_{(s)}$,$E^o_{RP} = -0.762 \, V$
$Cr^{3+}_{(aq)} + 3e^{-} \rightleftharpoons Cr_{(s)}$,$E^o_{RP} = -0.740 \, V$
$2H^{+}_{(aq)} + 2e^{-} \rightleftharpoons H_{2(g)}$,$E^o_{RP} = 0.00 \, V$
$Fe^{3+}_{(aq)} + e^{-} \rightleftharpoons Fe^{2+}_{(aq)}$,$E^o_{RP} = 0.77 \, V$

Given at $298 \ K$: $E^\ominus_{Fe^{2+}/Fe} = X \ V$; $E^\ominus_{Fe^{3+}/Fe} = Y \ V$. The $E^\ominus_{Fe^{3+}/Fe^{2+}}$ in Volt at $298 \ K$ is given by: