Iron(II)

Iron(II), also known as ferrous iron, represents the divalent cation of iron, Fe²⁺. It is a crucial component in various chemical and biological processes. In chemistry, iron(II) is a reducing agent, readily donating electrons to form iron(III) (Fe³⁺). Its compounds often exhibit a green or pale-blue color in solution, and are commonly found in minerals and synthetic compounds used in industries and laboratories. In biology, iron(II) is a vital cofactor for enzymes, such as cytochrome oxidase and catalase, playing a role in oxygen transport and metabolism. The properties of iron(II) compounds are influenced by their counterions, ligands, and environmental conditions. iron(II) is a fundamental part of many common processes.

Iron(II) meaning with examples

• In the laboratory, ferrous sulfate (iron(II) sulfate) is frequently used as a source of iron(II) ions in the synthesis of other iron-containing compounds or as a reducing agent. It reacts with oxidizing agents, such as potassium permanganate, becoming iron(III) sulfate. The resulting changes in color can be used to determine the concentration of the substances involved in reactions.
• The oxygen-carrying capacity of hemoglobin in red blood cells is dependent on the presence of iron(II) within the heme group. This allows for the effective transport of oxygen throughout the body. The iron(II) atom binds with oxygen, and the amount available has a significant effect on the blood's ability to fulfill this function.
• Corrosion of iron metal, such as the rusting of steel, often involves the oxidation of iron to iron(II) ions. The resulting iron(II) oxide or hydroxide forms a reddish-brown layer on the surface. These reactions require oxygen and water, leading to gradual degradation of the iron.
• In wastewater treatment, iron(II) salts are used as coagulants to remove phosphates and other pollutants. The iron(II) ions react with the pollutants to form insoluble precipitates that can be filtered out. This helps to reduce the environmental impact of the substances.