What chemical reaction is rust?

what chemical reaction is rust?

Rust is the name of Iron oxides that form as the consequence of the Corrosion process of Steel (Iron). Corrosion can be defined as the destructive attack of a metal through interaction with its environment.

Electrochemical corrosion is the most important mechanism that causes  Rust on Metal.

Four conditions must exist before electrochemical corrosion can proceed and metal rust:

(1) there must be something that rusts , the metal anode, where the oxydation reaction take places

(2) there must be a cathode, where the reduction reaction take places

(3) there must be continuous conductive liquid path (electrolyte, usually condensate and salt or other contaminations), for example: water, seawater, condensing water, humidity..

(4) there must be a conductor to carry the flow of electrons from the anode to the cathode.