The speicies that undergoes disproportionation in an alkaline medium is

Options

A. `MnO_(4)^(2-)`
B. `ClO_(4)^(-)`
C. `NO_(2)`
D. All of these

Answer

C

Explanation

`2NO_(2) (g) + 2OH^(-) (aq) rarr NO_(2)^(-) (aq) + NO_(3)^(-) (aq) + H_(2)O (l)` ltbr. This reaction involves disproportionation of `NO_(2)` (`+4` state) in to `NO_(2)^(-)` (+3 state) and `NO_(3)^(-)` (+5 state). Therefore, this reaction is an example of disproportionation redox reaction.