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 perchlorate employing gases under pressure, as the water must be removed from the air prior to the reaction taking place. Barium perchlorate is also used for the determination of small concentrations (down to 10 ppm, with an accuracy of +/- 1 ppm) of sulfate. In order for the titration to be successful, a high concentration of a nonaqueous solvent, such as ethyl alcohol, 2-propanol, or methanol, must be present. Thorin is typically used as the indicator. Barium perchlorate Barium perchlorate is a powerful oxidizing agent, with the formula Ba(ClO). It is used in the pyrotechnic industry. Barium perchlorate decomposes at 505