Rusting of iron is an illustration of a redox reaction.
Iron reacts with oxygen in the presence of water to rust.
The oxidizing ingredient in this oxidation process is oxygen.
A reduction process also takes place in which the metal iron serves as a reducing agent since oxygen also reacts with it. The process through which iron oxides, which make up rust, develop on the surface of iron objects or structures.
When oxygen and iron are exposed to a water-containing environment, such as the air with a lot of moisture, rust is created.