Explain the oxidising property of `KMnO_(4)` in neutral medium .Give the equations.

Explanation

Potassium permanganate is a strong oxidising agent , its oxidising action differs in different reaction medium.
In neutral medium :
In neutral medium it is reduced to `MnO_(2)`
`MnO_(4)^(-) + 2H_(2) O + 3e^(-) to MnO_(2) + 4OH^(-)`
(i) It oxidises `H_(2)` S to sulphur
`2MnO_(4) ^(-) + 3H_(2) S to`
`2MnO_(2)+ 3S + 2OH^(-) + 2H_(2) O`
(ii) It oxidises thiosulphate into sulphate
`8MnO_(4)^(-) + 3S_(2) O_(3)^(2-) + H_(2)(O to `
`6SO_(4)^(2-) + 8MnO_(2) + 2OH^(-)`