Fireworks is released at once. Similar to a chrysanthemum, but with long-burning silver or gold stars that produce a soft, dome-shaped weeping willow-like effect. Fireworks pose risks of injury to people, and of damage, largely as a fire hazard. Fireworks produce smoke and dust that may contain residues of heavy metals, sulfur-coal compounds and some low concentration toxic chemicals. These by-products of fireworks combustion will vary depending on the mix of ingredients of a particular firework. (The color green, for instance, may be produced by adding the various compounds and salts of barium, some of which are toxic, and some of
Barium carbonate barium sulfide either by treatment with sodium carbonate at 60 to 70 °C (soda ash method) or by passing carbon dioxide at 40 to 90 °C. In the soda ash process, solid or dissolved sodium carbonate is added to barium sulfide solution, and the barium carbonate precipitate is filtered, washed and dried. Barium carbonate reacts with acids such as hydrochloric acid to form soluble barium salts, such as barium chloride: However, the reaction with sulfuric acid is poor, because barium sulfate is highly insoluble. Barium carbonate is widely used in the ceramics industry as an ingredient in glazes. It acts