Main page (Russian) Search in database (English)

Properties of substance:

phosphonic acid

Group of substances:

inorganic

Physical appearance:

colorless crystals

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

H3O3P

Structural formula as text:

(HO)2P(O)H

Molar/atomic mass: 81.996

Melting point (°C):

70.1

Decomposition temperature (°C):

200

Solubility (g/100 g of solvent):

ethanol: soluble [Ref.]
water: 309 (0°C) [Ref.]
water: 694 (30°C) [Ref.]

Hygroscopic:

very hygroscopic

Density:

1.65 (21°C, g/cm3)

Dissociation:

pKa (1) = 1.257 (25°C, water)
pKa (2) = 6.7 (25°C, water)

Standard molar enthalpy (heat) of formation ΔfH0 (298.15 K, kJ/mol):

-952.3 (s)

Molar enthalpy (heat) of fusion ΔfusH (kJ/mol):

15.5

LD50 (mg/kg):

1700 (, oral)

References:

  1. Гринвуд Н., Эрншо А. Химия элементов. - Т.1. - М.: БИНОМ. Лаборатория знаний, 2008. - pp. 476-479 [Russian]
  2. Краткая химическая энциклопедия. - Т. 5: Т-Я. - М.: Советская энциклопедия, 1967. - pp. 509 [Russian]
  3. Некрасов Б.В. Основы общей химии. - Т.1. - М.: Химия, 1973. - pp. 446 [Russian]
  4. Постников Н.Н. Термическая фосфорная кислота. Химия и технология. - М.: Химия, 1970. - pp. 50-52 [Russian]
  5. Рабинович В.А., Хавин З.Я. Краткий химический справочник. - Л.: Химия, 1977. - pp. 109 [Russian]
  6. Токсикологический вестник. - 1995. - №6. - pp. 38 [Russian]

    What information do you need?




    © Collected Ruslan Anatolievich Kiper, burewestnik@mail.ru