Why is Rusting Iron a Redox Reaction?

-Iron will lose 3 Electrons, when it Reacts with Oxygen, to become an Ion with a 3+ Charge. This is Oxidation -Oxygen will gain 2 Electrons, when it Reacts with Iron, to become an Ion with a 2- Charge. This is Reduction -And a Redox Reaction is when both Oxidation and Reduction is Present.