Barium peroxide Barium peroxide Barium peroxide is the inorganic compound with the formula BaO. This white solid (gray when impure) is one of the most common inorganic peroxides, and it was the first peroxide compound discovered. Being an oxidizer and giving a vivid green colour upon ignition (as do all barium compounds), it finds some use in fireworks; historically, it was also used as a precursor for hydrogen peroxide. Barium peroxide is a peroxide, containing subunits. The solid is isomorphous to calcium carbide, CaC. Barium peroxide arises by the reversible reaction of O with barium oxide. The peroxide forms around 500 °C
Barium bromide over a short period of time Barium bromide can be crystallized out from the solution in its dihydrate form, BaBr·2HO, which gives the anhydrous form upon heating to 120 °C. Barium bromide is a precursor to chemicals used in photography and to other bromides. Historically, barium bromide was used to purify radium in a process of fractional crystallization devised by Marie Curie. Since radium precipitates preferentially in a solution of barium bromide, the ratio of radium to barium in the precipitate would be higher than the ratio in the solution. Barium bromide, along with other water-soluble barium salts, is toxic