# The change in oxidation state of Mn element in the reaction , 3MnO4²- + 4H+→ MnO2+2MnO4- + 2H2O is? Please help me, thanks.

Permanganate ion is reduced from $M n \left(V I I +\right)$ to $M n \left(I V +\right)$ in the oxide.
$M n {O}_{4}^{-} + 4 {H}^{+} + 3 {e}^{-} \rightarrow M n {O}_{2} + 2 {H}_{2} O$
This is balanced with respect to mass and charge. However, permanganate is normally reduced to $M {n}^{2 +}$, which is almost colourless. In fact, this reduction reaction is self indicating in that permanganate is intensely coloured.