The chemical formula for rust is Fe2O3. Rust is formed when iron reacts with oxygen in moist air. The following chemical equation represents the reaction: 4Fe + 3O2 → 2Fe2O3.
Let's return to the chemical reaction in which iron (Fe) combines with oxygen (O2) to form rust, or iron oxide (Fe2O3). The equation for this reaction is: 4Fe+ 3O2 → 2Fe2O.
