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 hydroxide to be free of carbonate, unlike those of sodium hydroxide and potassium hydroxide, as barium carbonate is insoluble in water. This allows the use of indicators such as phenolphthalein or thymolphthalein (with alkaline colour changes) without the risk of titration errors due to the presence of carbonate ions, which are much less basic. Barium hydroxide is occasionally used in organic synthesis as a strong base, for example for the hydrolysis of esters and nitriles, and as a base in aldol condensations. It has been used to hydrolyse one of the two equivalent ester groups in dimethyl hendecanedioate. Barium hydroxide is