orthofosfaationen

Orthofosfaationen are the orthophosphate anions, the deprotonated forms of orthophosphoric acid. In aqueous solution the phosphate system includes H3PO4, H2PO4−, HPO4^2− and PO4^3−, with PO4^3− representing the fully deprotonated form. The orthophosphate ion has a tetrahedral geometry around phosphorus and carries a -3 charge in the PO4^3− form. Acid–base equilibria at different pH determine which species predominate, with pKa values near 2.15, 7.20 and 12.37.

Orthofosfaationen are widespread in geology, biology, and water chemistry. They originate mainly from the weathering of phosphate minerals such as apatite and from biological turnover. In living organisms, orthophosphates are essential building blocks and energy carriers, forming components of DNA, RNA, ATP, and phospholipids. Plants and microorganisms take up soluble phosphate from soils and waters for growth.

Environmental and practical aspects of orthofosfaationen are closely tied to nutrient cycles and water quality. In natural waters, orthophosphate ions influence ecological dynamics and productivity. Excess phosphates from agricultural runoff and domestic detergents can trigger eutrophication, leading to algal blooms and oxygen depletion. Wastewater treatment often aims to remove orthophosphate via chemical precipitation with calcium, iron, or aluminum, or through adsorption and enhanced biological uptake.

Terminology and naming can vary by language. In English, the term orthophosphate is commonly used for the ion itself; orthofosfaationen, as a plural form, appears in some languages to denote phosphate anions collectively. The concept also encompasses partially protonated species such as H2PO4− and HPO4^2−, whose relative abundance depends on the pH of the environment.