An example for autocatalysis is

Options

A. oxidation of NO to `NO_(2)`
B. oxidation of `SO_(2)` to `SO_(3)`
C. decomposition of `KClO_(3)` to KCl and `O_(2)`
D. oxidation of oxalic acid by acidified `KMnO_(4)`

Answer

D

Explanation

`2KMnO_(4)+5H_(2)C_(2)O_(4)+3H_(2)SO_(4)rarr K_(2)SO_(4)+2MnSO_(4)+8H_(2)+10CO_(2)`
The pink colour of `KMnO_(4)` disappears slowly on treating it with oxalic acid, but the rate of disappearance of colour factens after sometime due to the formation of `Mn^(2+)` ions which acts as autocatalyst for the reaction.