Prove the following

If $\mathrm{E}_{\mathrm{ext}}>1.1 \mathrm{~V}, \mathrm{Zn}$ dissolves at $\mathrm{Zn}$

electrode and $\mathrm{Cu}$ deposits at $\mathrm{Cu}$ electrode

If $\mathrm{E}_{\text {ext }}>1.1 \mathrm{~V}, \mathrm{e}^{-}$flows from $\mathrm{Cu}$ to $\mathrm{Zn}$

If $\mathrm{E}_{e x t}=1.1 \mathrm{~V}$, no flow of $\mathrm{e}^{-}$or current occurs

If $\mathrm{E}_{\mathrm{ext}}<1.1 \mathrm{~V}, \mathrm{Zn}$ dissolves at anode and $\mathrm{Cu}$ deposits at cathode