Barium Hydroxide - Ba(OH)2

What is Barium Hydroxide?

Barium hydroxide is also called as baryta with the formula Ba(OH)2. It is a clear white powder with no odour. It is poisonous in nature. It is ionic in nature for example, Ba(OH)2 (barium hydroxide) in aqueous solution can provide two hydroxide ions per molecule. Barium hydroxide is the only reagent described for metalizing carboxamidesBarium hydroxide was less degradative as compared to barium oxide.

Other name – Caustic baryta, Barium dihydroxide, barium(2+) dihydroxide


Barium Hydroxide


3.74 g/cm³

Molecular Weight/ Molar Mass

171.34 g/mol

Boiling Point

780 °C

Melting Point

78 °C

Chemical Formula


Barium hydroxide Structure – Ba(OH)2

Barium Hydroxide

Physical Properties of Barium hydroxide – Ba(OH)2




White solid

Covalently-Bonded Unit


Vapour Pressure

0.48 kPa at 17.6 deg C




Slightly soluble in cold water

Uses of Barium hydroxide – Ba(OH)2

  • Barium hydroxide forms a strong caustic base in aqueous solution. It has many uses, e.g., as a test for sulfides; in pesticides; in the manufacture of alkali and glass.
  • Use of barium hydroxide lime rather than soda lime, high sevoflurane concentration, high absorbent temperature, and fresh absorbent use.
  • Used in the manufacture of alkalis, glass, oil and grease additives, barium soaps, and other barium compounds.

Health Hazard

  • Inhalation of barium dusts can cause irritation of the nose and upper respiratory tract and may produce a benign pneumoconiosis known as baritosis.
  • Barium ions are toxic to muscles especially heart, producing stimulation and then paralysis.
  • It is extremely dangerous neurotoxin. Adverse effect may result like effects on heart and the function of the central nervous system (CNS).

Practise This Question

Which of the following is a branched polymer?