It then becomes, in the presence of free oxygen, FE 2 O 3 which is what we call common rust. In electrolysis, acids and bases tend to cause current to flow like in batteries. In the generation of current, the atoms become ionized. Then the ionized iron is attracted to the oxygen molecules which in water is relatively electrically negative. At that point, it does the same as above.
Some bacteria can actually metabolize iron.
Chlorine, oxygen, and other compounds can cause direct corrosion without water. Cathodic protection - Use of a sacrificial electrode to supply electrons to the iron for the reduction of oxygen and slows process of corrosion. Selection of materials - Corrosion resistant materials like plastics, stainless steels, and brass. Bat Gate - Difference in where steel made in different places or stressed differently cause voltage similar to dissimilar metals.