Question

Standard potential (E°) of

\[\mathrm{Zn_{(aq)}^{+2}+2e^{-}\longrightarrow Zn_{(s)}~is~-0.76~V}\]

What is standard potential of reaction 

\[2\mathrm{Zn}_{(\mathrm{s})}\longrightarrow2\mathrm{Zn}_{(\mathrm{aq})}^{+2}+4\mathrm{e}^{-}\] ?

Options

• − 1.52 V

• + 1.52 V

• − 0.76 V

• + 0.76 V

Answer 1

+ 0.76 V

Explanation:

\[\mathrm{Zn_{(aq)}^{+2}+2e^{-}\longrightarrow Zn_{(s)};}\]

E^° = − 0.76 V

\[2\mathrm{Zn}_{(\mathrm{s})}\longrightarrow2\mathrm{Zn}_{(\mathrm{aq})}^{+2}+4\mathrm{e}^{-};\]

E^° = − ( −0.76 V) = + 0.76 V