Q. The standard potentials, at $ \text{25}{{\,}^{\text{o}}}\text{C,} $ for the half- reactions are given against them below : $ Z{{n}^{2+}}+2{{e}^{-}}\xrightarrow{{}}Zn $ $ {{E}^{o}}=-0.762\,V $ $ M{{g}^{2+}}+2{{e}^{-}}\xrightarrow{{}}Mg $ $ {{E}^{o}}=-2.37\,V $ When Zn dust is added to a solution of $ \text{MgC}{{\text{l}}_{\text{2}}}\text{,} $
EAMCETEAMCET 2009
Solution: