Gallic acid monohydrate

In the crystal structure of the title compound, 3,4,5-tri­hydroxy­benzoic acid monohydrate, C₇H₆O₅·H₂O, the gallic acid mol­ecule is essentially planar and has two intramolecular hydrogen bonds between hydroxyl groups. The H atoms of the three hydroxyl groups are oriented in the same direction around the ring, and form intra- and intermolecular hydrogen bonds. The crystal structure is stabilized by all available intermolecular hydrogen bonds, including also those involving the water mol­ecule.