Title: Selenic Acid

CAS Registry Number: 7783-08-6

Molecular Formula: H2O4Se

Molecular Weight: 144.97

Percent Composition: H 1.39%, O 44.15%, Se 54.47%

Line Formula: H2SeO4

Literature References: Prepd by treating lead selenate with hydrogen sulfide and concentrating the filtered soln by evaporation: Mitscherlich, Pogg. Ann. 9, 623 (1827); 11, 327 (1827); Ann. Chim. Phys. [2] 36, 100 (1827); by treating calcium selenate with cadmium oxalate and hydrogen sulfide: von Hauer, J. Prakt. Chem. [1] 80, 214, 317 (1860); by treating a soln of silver selenite with bromine and evaporating the filtered soln: Thomsen, Ber. 2, 598 (1869); by oxidizing selenium oxide with 30% hydrogen peroxide and removing water: Gilbertson, King, J. Am. Chem. Soc. 58, 180 (1936); Inorg. Synth. 3, 137 (1950).

Properties: Hexagonal prisms; mp 58°; d415 2.9508; bp 260°. Very sol in water; sol in sulfuric acid; insol in ammonia; dec in alcohol. Very deliquescent. Reduced by hydrobromic acid, hydriodic acid, hydrogen sulfide, hydroxylamine hydrochloride, phenylhydrazine, formic acid, oxalic acid, malonic acid, pyruvic acid, acetyl chloride, and several metals.

Melting point: mp 58°

Boiling point: bp 260°

Density: d415 2.9508