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Question
Complete the following reaction and justify that it is a disproportionation reaction:
\[\ce{3MnO^{2-}4 + 4H^+ -> \underline{}\underline{}\underline{}\underline{} + \underline{}\underline{}\underline{}\underline{} + 2H2O}\]
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Solution
\[\ce{3MnO^{2-}4 + 4H^+ -> 2MnO^-4 + MnO2 + 2H2O}\]
This is a disproportionation reaction since the same element [Mn] is oxidised and reduced in this process.
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| Fe3+/Fe2+ | +0.8 V |
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