# Please,why is MnO2-4 i.e manganese(vi)oxide not MnO3?...i still dont get it..i mean if u calculate the oxidation number with the latter it'll still be +6

Jun 24, 2018

The formula for manganese(VI) oxide is $M n {O}_{3}$

#### Explanation:

I'm not sure if I understand the question completely, but I'll verify the oxidation number and formula for $M n {O}_{2}$ and $M n {O}_{3}$

We know that the oxidation number for O is -2
Let's set the oxidation number for Mn as x

Manganese(VI) oxide is indeed $M n {O}_{3}$

$M {n}^{\text{6+}}$ ${O}^{\text{2-}}$ => $M {n}_{2} {O}_{6}$ => $M n {O}_{3}$

Oxidation number for Mn in $M n {O}_{3}$: x + 3(-2) = 0 => x = +6

Manganese(IV) oxide, on the other hand is $M n {O}_{2}$

$M {n}^{\text{4+}}$ ${O}^{\text{2-}}$ => $M {n}_{2} {O}_{4}$ => $M n {O}_{2}$

Oxidation number for Mn in $M n {O}_{2}$: x + 2(-2) = 0 => x = +4