The zinc helps prevent corrosion because it reacts with many chemicals more easily than iron does. However, if the iron has been galvanized, the zinc protects the iron by reacting with the oxygen and forming zinc oxide before rust can form.
Steel is the most commonly galvanized metal.
One simple and widely used method of applying a zinc coating to steel is called hot-dip galvanizing. This method involves dipping steel in a hot bath of liquid zinc. In some cases, steelmakers mix other metals, such as aluminum, antimony, cadmium, and tin, with the zinc. Manufacturers add such metals in order to improve the appearance or the protective qualities of the coating. Metal pails and similar small objects are dipped in the zinc bath and galvanized one at a time.