MG

Magnesium (symbol Mg) is a chemical element and the lightest structural metal. It is the eighth most abundant element in the Earth's crust and the third most abundant cation in seawater. Magnesium belongs to group 2 of the periodic table, the alkaline earth metals, and occurs naturally in minerals such as magnesite (MgCO3) and dolomite (CaMg(CO3)2) as well as in brines and seawater.

Physically, magnesium is a silvery-gray metal at room temperature, with a density of about 1.74 g/cm3, a melting point of 650°C, and a boiling point of 1090°C. It forms a thin oxide layer in air that slows further corrosion. It reacts with acids and, more slowly, with water to release hydrogen gas. When ignited, magnesium burns with a bright white flame and forms magnesium oxide.

The most common oxidation state of magnesium is +2. Industrially, magnesium is produced mainly by electrolysis of molten magnesium chloride, which is derived from seawater or brines. Magnesium is also used in the processing of other magnesium-containing minerals. It readily forms alloys, particularly with aluminum, zinc, and other elements, producing lightweight materials for aerospace, automotive, and electronics.

Biologically, Mg2+ is an essential cofactor for hundreds of enzymes and is critical for stabilizing DNA, RNA, and ATP structures. It plays a role in nerve function, muscle contraction, and bone development. In humans, magnesium intake is necessary for health, with deficiency leading to cramps or metabolic disturbances in extreme cases.

Applications and uses include lightweight magnesium alloys, fireworks and flares due to bright combustion, refractory linings in high-temperature furnaces, and various dietary supplements and medicinal magnesium salts. Isotopes of magnesium in nature are Mg-24, Mg-25, and Mg-26.