How is potassium permanganate `( KMnO_4)` prepared from `MnO_2` ? write the equation.

Explanation

Preparation of `KMnO_4` : Potassium permanganate is prepared by the fusion of`MnO_2` with alkali metal hydroxide and an oxidizing agent like `KNO_3`.Its forms of dark green `K_2MnO_4` which disproportionates in a neutral of acidic solution to give permanganate.
(i)`2MnO_2+4KOH+O_2 overset(KNO_3)to2K_2MnO_4+2H_2O`
(ii)`3MnO_4^(2-)+4H^+ to 2MnO_4^(-)+MnO_2+2H_2 or 3K_2 MnO_4+2H_2SO_4 to2KMnO_4` potassium parmangnate.