Mg2Ionen

Mg2Ionen, commonly written Mg2+ ions in English, are the magnesium cation with a 2+ charge, arising from the loss of two electrons from neutral magnesium atoms (atomic number 12). In most compounds magnesium exists predominantly in the Mg2+ state. Because Mg2+ is small and highly charged, it behaves as a hard Lewis acid and is strongly hydrated in aqueous solutions.

In water, Mg2+ forms a hexaaqua complex, [Mg(H2O)6]2+, and the ion adopts an octahedral coordination geometry. Its hydration shells give it high lattice and hydration energies, which influence solubility, crystal structure, and hydrolysis behavior. Hydrolysis of the aqua ligands can generate MgOH+ species at higher pH, affecting magnesium's speciation in natural waters.

Biological role: Mg2+ is an essential micronutrient for all organisms. It acts as a cofactor for hundreds of enzymes, stabilizes ribosomes and nucleic acids, and participates in energy transfer through interactions with ATP. Magnesium also helps stabilize the structures of chlorophyll in plants and contributes to charge stabilization in nucleic acids' backbone.

Occurrence and minerals: magnesium is abundant in the Earth's crust and seawater. Common magnesium-containing minerals include magnesite (MgCO3) and brucite (Mg(OH)2); dolomite is a calcium-magnesium carbonate (CaMg(CO3)2). In nature Mg2+ is found in dissolved ionic form in water and soil minerals.

Applications and health: Mg2+ salts such as MgCl2 and MgSO4 are used in chemistry, medicine, agriculture, and industry. Magnesium supplementation is used to treat deficiency and prevent cramps, though excessive intake can cause adverse effects. In environmental contexts Mg2+ levels influence water hardness and biological processes.