phosphat

Phosphat, commonly spelled phosphate in many languages, designates chemical species derived from phosphoric acid. The term covers the inorganic phosphate ion PO4^3−, its protonated forms, and a broad family of salts and esters found in geology, biology, and industry.

In aqueous solutions, phosphate exists mainly in three protonation states: orthophosphate (PO4^3−), hydrogen phosphate (HPO4^2−), and dihydrogen phosphate (H2PO4−). Each form participates in acid–base equilibria with pKa values about 2.15, 7.20, and 12.35. Phosphates also form polyphosphates and phosphate esters, which feature chains or networks of P–O–P linkages.

Naturally, phosphates occur in minerals such as the apatite group and in biological systems. They are central to energy transfer (ATP, GTP), genetic material (DNA, RNA backbones), and signaling through protein phosphorylation. Calcium phosphate forms hydroxyapatite, a major mineral in bone and teeth, contributing to structural support.

Environmentally and economically important, phosphates are mined from phosphate rock to produce fertilizers and animal feeds. They are widely used in detergents, food and beverage additives, and industrial processing. Because phosphates are essential but finite, their management affects agriculture, water quality, and supply security. Runoff containing phosphates promotes eutrophication and algal blooms in aquatic ecosystems, prompting regulation and recycling initiatives.

In short, phosphat/phosphate encompasses a versatile class of molecules with roles in biology, geology, and industry, while also presenting environmental and resource-management challenges.