Write the ionic equations for the oxidizing action of $\mathrm{MnO_4^-}$ in acidic medium for :
(I) $\mathrm{Fe^{2+}}$ ion
(II) $\mathrm{C_2O_4^{2-}}$ ion
(I) $\mathrm{Fe^{2+}}$ ion
(II) $\mathrm{C_2O_4^{2-}}$ ion
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Solution and Explanation
(II) answer: In the same way $\mathrm{MnO_4^-}$ oxidises oxalate $\mathrm{C_2O_4^{2-}}$ to carbon dioxide, while it is reduced to $\mathrm{Mn^{2+}}$. Balancing the electrons gives two permanganate ions reacting with five oxalate ions:\[ 2MnO_4^- + 16H^+ + 5C_2O_4^{2-} \rightarrow 2Mn^{2+} + 10CO_2 + 8H_2O \]
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