bariumoxide

Barium oxide (BaO) is an inorganic compound and the oxide of the alkaline earth metal barium. It is a white, hygroscopic solid that adopts a face-centered cubic lattice similar to sodium chloride. It has a high melting point and a basic character typical of metal oxides.

Production and occurrence: BaO is principally prepared by calcination of barium carbonate (BaCO3) at elevated temperature, which drives off carbon dioxide: BaCO3 → BaO + CO2. Alternative routes include decomposition of other barium compounds. In air, BaO slowly reacts with CO2 and moisture to form barium carbonate and hydroxide on the surface.

Chemical properties: It reacts vigorously with water to form barium hydroxide, Ba(OH)2, releasing heat: BaO + H2O → Ba(OH)2. It also forms Ba salts with acids and slowly carbonates in air to re-form BaCO3. BaO is highly basic and reacts with acidic gases; it is not very soluble in water, but the resulting Ba(OH)2 is highly soluble.

Uses: BaO is used as a drying agent for gases and solvents due to its moisture-absorbing properties. In ceramics and glassmaking it can act as a flux and whiteness enhancer, and it serves as a precursor to other barium compounds in the chemical industry. It is also employed as a source of Ba2+ in certain laboratory preparations.

Safety: Barium oxide is caustic and toxic if ingested. It reacts with moisture to form caustic Ba(OH)2, which can cause severe burns. Handle under dry conditions; avoid inhalation of dust; store in sealed, moisture-free containers and dispose of according to regulations.