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प्रश्न
Explain why does colour of \[\ce{KMNO4}\] disappear when oxalic acid is added to its solution in acidic medium.
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उत्तर
\[\ce{KMnO4}\] acts as oxidising agent. It oxidises oxalic acid to \[\ce{CO2}\] and itself changes to \[\ce{Mn^2+}\] ion which is colourless.
\[\ce{5C2O^{2-}4 + \underset{(Coloured)}{2MnO^-4} + 16H+ -> \underset{(Coloured)}{2Mn^2+} + 8H2O + 10CO2}\]
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|
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