# Oxygen almost always has an oxidation number of -2. Therefore in the formula for the mineral wüstite, #FeO#, what must the oxidation number for iron be? In the formula for hematite, #Fe_2O_3#, what must the oxidation number for iron be?

##### 1 Answer

May 13, 2017

Actually oxygen usually has an oxidation number of

#### Explanation:

In its oxides, an oxidation number of

The