Iron reacts with atmospheric oxygen to form iron oxide or ferric oxide. Look at the chemical equation for this reaction:

Fe + O2 → Fe2O3

This equation is unbalanced. Which of the following is the correct balanced equation for this reaction?

A.
4Fe + 3O2 → 2Fe2O3
B.
3Fe + 4O2 → 2Fe2O3
C.
2Fe + 4O2 → 3Fe2O3
D.
3Fe + 3O2 → 4Fe2O3
E.
4Fe + 4O2 → 3Fe2O3