Barium nitrate fighters, such as the Hawker Hurricane and Supermarine Spitfire, during the Battle of Britain. It is also used in the manufacturing process of barium oxide, the vacuum tube industry and for green fire in pyrotechnics. Like all soluble barium compounds, barium nitrate is toxic by ingestion or inhalation. Solutions of sulfate salts such as Epsom salts or sodium sulfate may be given as first aid for barium poisoning, as they precipitate the barium as the insoluble (and non-toxic) barium sulfate. Inhalation may also cause irritation to the respiratory tract. While skin or eye contact is less harmful than ingestion or
Barium hydroxide used, as well, in the decarboxylation of amino acids liberating barium carbonate in the process. It is also used in the preparation of cyclopentanone, diacetone alcohol and -Gulonic γ-lactone. Barium hydroxide decomposes to barium oxide when heated to 800 °C. Reaction with carbon dioxide gives barium carbonate. Its aqueous solution, being highly alkaline, undergoes neutralization reactions with acids. Thus, it forms barium sulfate and barium phosphate with sulfuric and phosphoric acids, respectively. Reaction with hydrogen sulfide produces barium sulfide. Precipitation of many insoluble, or less soluble barium salts, may result from double replacement reaction when a barium hydroxide aqueous solution