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 is then reduced by carbon to barium sulfide: The water-soluble barium sulfide is the starting point for other compounds: reacting BaS with oxygen produces the sulfate, with nitric acid the nitrate, with carbon dioxide the carbonate, and so on. The nitrate can be thermally decomposed to yield the oxide. Barium metal is produced by reduction with aluminium at . The intermetallic compound BaAl is produced first: BaAl is an intermediate reacted with barium oxide to produce the metal. Note that not all barium is reduced. The remaining barium oxide reacts with the formed aluminium oxide: and the overall reaction is