According to Chemical Dictionary, the chemical formula for barium bromide is BaBr2. The chemical compound is described as white orthorhombic crystals. It is water-soluble and toxic in aqueous solution.
Marie Curie used barium bromide in the process of fractional crystallization to purify radium. Radium precipitates conversely in a solution of BaBr2. As a result, the ratio of radium to barium was higher than the ratio within the solution.
Barium bromide reacts with sulfate ions from sulfuric acid. The product is barium sulfate. Comparable reactions also occur with phosphoric acid, oxalic acid and hydrofluoric acid.
Barium bromide is used in the manufacture of other bromides and as a precursor to chemicals used in photography.