Copper(II) chlorate heated, giving off a yellow gas, which contains chlorine, oxygen and chlorine dioxide. A green solid is left that is a basic copper salt. Sulfur is highly reactive with copper chlorate, and it is important not to cross contaminate these chemicals, for example in pyrotechnic making. François-Marie Chertier used tetrammine copper chlorate to colour flames blue in 1843. This material was abbreviated TACC with formula Cu(NH)(ClO). TACC explodes on impact. The substance became known as Chertier'c copper for use in blue coloured pyrotechnics. However its deliquescence causes a problem. Mixtures with other metal salts can yield violet or lilac colours
Barium bromide and can cause severe poisoning if ingested. Barium bromide Barium bromide is the chemical compound with the formula BaBr. Like barium chloride, it dissolves well in water and is toxic in aqueous solution. BaBr crystallizes in a lead chloride motif, giving white orthorhombic crystals which are deliquescent. In aqueous solution BaBr behaves as a simple salt. Barium bromide reacts with the sulfate ion from sulfuric acid to produce a precipitate of barium sulfate. Similar reactions occur with oxalic acid, hydrofluoric acid, and phosphoric acid. Barium bromide can be prepared from barium sulfide or barium carbonate via reaction with hydrobromic acid