A phosphorus oxoacid that consists of one oxo and three hydroxy groups joined covalently to a central phosphorus atom. ChEBI: Phosphoric acid is a phosphorus oxoacid that consists of one oxo and three hydroxy groups joined covalently to a central phosphorus atom. It has a role as a solvent, a human metabolite, an algal metabolite and a fertilizer. It is a conjugate acid of a dihydrogenphosphate and a phosphate ion.