oxidation-reduction question..
MnO4(2-)
Mn+4(-2)=-2
Mn=+6
....
Mn2O3
2Mn+3(-2)=0
Mn=+3

Why is it first =-2 and then for the Mn2O3=0

**I understand the rules for the first one I dont for the second one..
thanks

Question

oxidation-reduction question..
MnO4(2-)
Mn+4(-2)=-2
Mn=+6
....
Mn2O3
2Mn+3(-2)=0
Mn=+3

Why is it first =-2 and then for the Mn2O3=0

**I understand the rules for the first one I dont for the second one..
thanks

anonymous · Answer

It has a charge on the first one. That's really it.

anonymous · Answer

It's an anion in the first one.

anonymous · Answer

For the first one b/c its a polyatomic ion we use the charge?

anonymous · Answer

They're both polyatomics (molecules made of multiple atoms), it just so happens that the first one has a charge. Polyatomics often have charges, but in some instances will be neutral. We get the charges by using the oxidation numbers.