The Iron atom got oxidized.
In inorganic chemistry Oxidation and Reduction reactions are defined as,
Reduction:
The reaction in which an atom accepts electrons is known as reduction reaction.
Example:
2 Na + Cl₂ → 2 NaCl
In this reaction Chlorine oxidation state has changed from 0 to -1. Hence, it has gained one electrons therefore, it is designated as being reduced.
Oxidation:
The reaction in which an atom looses electrons is known as reduction reaction.
Examples:
2 Na + Cl₂ → 2 NaCl
In this reaction Sodium's oxidation state has changed from 0 to +1. Hence, it has lost one electrons therefore, it is designated as being Oxidized.
2 Fe + 3 O₂ → 2 FeO
In this reaction Iron's oxidation state has changed from 0 to +2. Hence, it has lost two electrons therefore, it is designated as being Oxidized.
