Question

Valency of manganese in MnO2

Answer 1

Answer:

Since O is 2- in valency and there are 2 O in MnO2, the O2 component represents a total valency of 4- (2 x 2 = 4). For MnO2 to be electrically neutral in this format, Mn must have a valency of 4+.

Answer 2

Answer:

It is actually very easy to get.

MnO2 -

If you remember the cross method , we exchange the valency while writing the formula.

So , Oxygen's valency is always -2.

But Mn has variable valency, sometimes +2 or sometimes +4

Mn      O

x           -2

So in this case Mn should have a valency of +4.

The compound then actually will become Mn2O4

and by simplifying we'll get Mno2.