Iron (Fe²⁺) is a positively charged ion of iron, which is a common metal found in the Earth's crust. It plays a crucial role in various biological processes, including oxygen transport in the blood. In its ferrous form (Fe²⁺), iron is soluble in water and can easily be absorbed by living organisms. In addition to its biological importance, Fe²⁺ is also significant in industrial applications. It is used in the production of steel and other alloys, contributing to the strength and durability of materials. The presence of iron compounds is essential in many chemical reactions, making it a vital element in both nature and industry.