What is the chemical formula of ordinary rust that forms on iron surfaces exposed to moist air?

💡 Solution & Explanation

Rust is hydrated ferric oxide represented chemically as Fe2O3 times xH2O, formed through the electrochemical oxidation of iron in the presence of oxygen and moisture. Magnetite is represented by Fe3O4, and wustite is FeO. Iron sulfide is a different mineral compound entirely. Galvanization is a preventive technique involving zinc coating to protect iron from rusting.