Phenylarsonic acid
![](/Images/godic/202502/02/PhAsO3H23254.png")
![Ball-and-stick model of the phenylarsonic acid molecule](/Images/godic/202502/02/Phenylarsonic_acid_molecule_ball3254.png")
Phenylarsonic acid is the chemical compound with the formula C6H5AsO(OH)2, commonly abbreviated PhAsO3H2. This colourless solid is an organic derivative of arsenic acid, AsO(OH)3, where one OH group has been replaced by a phenyl group. The compound is a buffering agent and a precursor to other organoarsenic compounds, some of which are used in animal nutrition, e.g. 4-hydroxy-3-nitrobenzenearsonic acid.