The chemical change that occurs during rusting is the result of iron reacting with oxygen and moisture in the environment, forming iron oxides. Rusting is an electrochemical process and typically occurs when iron is exposed to air and water over time. The formation of rust (iron(III) oxide) not only deteriorates the metal but also indicates the underlying reactions taking place. Preventing rust, often through coatings or galvanization, is essential for prolonging the lifespan of iron-based materials and structures.