Standard potential of electrode reaction $\mathrm{Cu}_{(\mathrm{aq})}^{+2}+2 \mathrm{e}^{-} \longrightarrow \mathrm{Cu}_{(\mathrm{s})}$ is +0.34 V .
What is standard potential of reaction
$$ 2 \mathrm{Cu}_{(\mathrm{s})} \longrightarrow 2 \mathrm{Cu}_{(\mathrm{aq})}^{+2}+4 \mathrm{e}^{-} ? $$
What is value of $E_{\text {cell }}$ at 298 K for the reaction, $\mathrm{Zn}_{(\mathrm{s})}+\mathrm{Cu}^{+2}(0.1 \mathrm{M}) \longrightarrow \mathrm{Zn}^{+2}(0.1 \mathrm{M})+\mathrm{Cu}_{(\mathrm{s})}$ if $\mathrm{E}_{\text {cell }}^{\circ}=1.1 \mathrm{~V}$ ?
$$ \begin{aligned} & \text { If } \mathrm{E}^{\circ}\left(\mathrm{Fe}_{(\mathrm{aq})}^{+2} \mid \mathrm{Fe}_{(\mathrm{s})}\right)=-0.44 \mathrm{~V} \text { and } \\ & \mathrm{E}^{\circ}\left(\mathrm{Sn}_{(\mathrm{aq})}^{+2} \mid \mathrm{Sn}_{(\mathrm{s})}\right)=-0.14 \mathrm{~V} \end{aligned} $$
What is standard emf of cell containing the two electrodes?
If $\mathrm{E}^o{}\left(\mathrm{AI}_{(\mathrm{eq})}^{+3} \mid \mathrm{AI}_{(\mathrm{s})}\right)=-1.66 \mathrm{~V}$. What is potential of $\mathrm{Al}_{(\mathrm{s})} \longrightarrow \mathrm{Al}^{+3}(0 \cdot 1 \mathrm{M})+3 \mathrm{e}^{-}$at 298 K ?