When KMnO_4 solution is added to hot oxalic acid solution, the de… - Vidyadip

MCQ

When $KMnO_4$ solution is added to hot oxalic acid solution, the decolourisation is slow in the beginning but becomes instantaneous after some time. This is because

✓
$Mn^{2+}$ acts as auto catalyst
B
$CO_2$ is formed
C
Reaction is exothermic
D
$MnO_4^-$ catalyses the reaction.

✓

Answer

Correct option: A.

$Mn^{2+}$ acts as auto catalyst

a
Here, $KMnO _4$ is a reactant in the reaction which forms $Mn ^{2+}$ which acts as an auto-catalyst. The reaction is slow initially because $MnO _4{ }^{-}$is getting converted to $Mn ^{2+}$ but once $Mn ^{2+}$ forms, the reaction becomes faster due to the catalytic action.

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