Barium oxalate Barium oxalate Barium oxalate (BaCO), a barium salt of oxalic acid, is a white odorless powder that is sometimes used as a green pyrotechnic colorant generally in specialized pyrotechnic compositions containing magnesium. Though largely stable, barium oxalate can be reactive with strong acids. A mild skin irritant, the substance is considered toxic when ingested, causing nausea, vomiting, renal failure, and injury to the gastrointestinal tract. It is different from most pyrotechnic colorants in that it is a reducing agent and not an oxidizing agent. It is extremely insoluble in water and converts to the oxide form when heated. The raw
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