Here's the breakdown of the reactants and products in the reaction of iron and oxygen to form iron oxide:

* Reactants:

* Iron (Fe): A metallic element.

* Oxygen (O₂): A diatomic gas.

* Product:

* Iron Oxide (Fe₂O₃): This is a compound, also known as rust, which is a reddish-brown solid.

The chemical equation for this reaction is:

4Fe + 3O₂ → 2Fe₂O₃