The structural formula of the phosphoric acid functional group in an acidic solution. In an alkaline solution, this functional group will release two hydrogen atoms and ionize the phosphate
with a formal charge of -2. Phosphate
ion is a polyatomic ion, which contains one phosphorus atom and is surrounded by four oxygen atoms to form a regular tetrahedron. Phosphate ion has a formal charge of -3 and is the conjugate base of hydrogen phosphate ion; hydrogen phosphate ion is the conjugate base of dihydrogen phosphate ion; and dihydrogen phosphate ion is the conjugate base of phosphoric acid Alkali. It is a hypervalent molecule (the phosphorus atom has 10 electrons in its valence shell). Phosphate is also an organophosphorus compound, its chemical formula is OP(OR)3.
Except for some alkali metals, most phosphates are insoluble in water under standard conditions.
In the diluted aqueous solution, phosphate exists in four forms. In a strong alkaline environment, there will be more phosphate ions; in a weak alkaline environment, there will be more hydrogen phosphate ions. In a weak acid environment, dihydrogen phosphate ions are more common; in a strong acid environment, water-soluble phosphoric acid is the main existing form.