iron ion

An iron ion is an atom of iron that has gained or lost electrons, resulting in a net electrical charge. The most common oxidation states for iron ions are +2 (ferrous) and +3 (ferric). These ions are crucial in biological systems, particularly in oxygen transport and electron transfer reactions, as seen in hemoglobin. Iron oxides, such as hematite and magnetite, are chemical compounds formed from iron and oxygen. In chemistry, the oxidation number of an ion indicates the number of electrons it has gained or lost to form a chemical bond. For example, the Fe³⁺ ion has an oxidation number of +3.1234