Main page (Russian) Search in database (English)

Properties of substance:

arsenic acid hemihydrate

Group of substances:

inorganic

Physical appearance:

colorless crystals

Empirical formula (Hill's system for organic substances):

H8As2O9

Structural formula as text:

(H3AsO4)2 * H2O

Molar/atomic mass: 301.9

Melting point (°C):

35.5

Decomposition temperature (°C):

120

Solubility (g/100 g of solvent):

ethanol: soluble [Ref.]
glycerol: soluble [Ref.]
water: soluble [Ref.]

Hygroscopic:

yes

Density:

2.5 (20°C, g/cm3)

Reactions:

  1. Yeild 33%. [Ref.1, Ref.2aster, Ref.3aster, Ref.4aster, Ref.5aster]
    C6H5OH + H3AsO4 → HOC6H4As(O)(OH)2 + H2O
    HOC6H4As(O)(OH)2 + NaOH → HOC6H4As(O)(OH)(ONa) + H2O

Dissociation:

pKa (1) = 2.22 (25°C, water)
pKa (2) = 6.98 (25°C, water)
pKa (3) = 11.41 (18°C, water)

LD50 (mg/kg):

6 (rabbits, intravenous)

References:

  1. Lewis R.J. Sax's Dangerous Properties of Industrial Materials. - 11ed. - Wiley-interscience, 2004. - pp. 299
  2. Seidell A. Solubilities of inorganic and metal organic compounds. - 3ed., vol.1. - New York: D. Van Nostrand Company, 1940. - pp. 112-113
  3. Рабинович В.А., Хавин З.Я. Краткий химический справочник. - Л.: Химия, 1977. - pp. 83 [Russian]
  4. Реми Г. Курс неорганической химии. - Т.1. - М., 1963. - pp. 706-708 [Russian]

    What information do you need?




    © Collected Ruslan Anatolievich Kiper, burewestnik@mail.ru