Oxidation reaction involves loss of electrons, and reduction reaction involves gain of electrons. The reaction in which a species disproportinates into two oxidation states ( lower and higher) is called disproportionation reaction.
Which of the following statements is wrong?

Options

A. Acidified `KMnO_(4)` solutions decolourises on the addition of sodium oxalate.
B. In the reaction between `Br_(2)` and `CsI, Br_(2)` is an oxidising agent and `CsI` is a reducing agent.
C. In the reaction `2K_(2)S_()O_(3)+I_(2)rarr2KI+K_(2)S_(4)O_(6)`, the change in the oxidation number of `S` is `0.5`.
D. `C` has the same oxidation number in both `CH_(4)` and `CO_(2)`

Answer

D

Explanation

a. The purple colour of `KMnO_(4)` is decolourised due ot the reduction of `MnO_(4)^(ө)` to `Mn^(2+)` and `C_(2)O_(4)^(2-)` is oxidised to `CO_(2)` in acidic medium.
`2MnO_(4)^(ө)+16H^(o+)+5C_(2)O_(4)^(2-)rarr2Mn^(2+)+10CO_(2)+8H_(2)O`
b.
c. `ul(C)H_(4):x+4=0, x= -4`
`ul(C)O_(2):x-4=0, x=4`