Also found in: Dictionary, Thesaurus, Medical, Wikipedia.
barium hydroxide[′bar·ē·əm hī′dräk‚sīd]
caustic baryta, Ba(OH)2, a base (alkali). Under ordinary conditions it exists in the form Ba(OH)2-8H20—colorless crystals with a density of 2.18 g/cm3. At 78° C it melts in its own water of crystallization. It is readily soluble in water (3.5g BaO in 100 g H20 at 20° C). The aqueous solution has a strongly alkaline reaction. The saturated aqueous solution of barium hydroxide at ordinary temperatures is called baryta water; upon contact of this solution with air, it absorbs CO2 and becomes turbid owing to the precipitation of barium carbonate. Barium hydroxide is a sensitive reagent for carbonate and sulfate ions. It initiates polymerization reactions and is also used in the production of sugar.