Barium bromide (BaBr2)
Barium bromide is a bromide of barium and bromine. It is a precursor to chemicals used in photography and to other bromides. Barium is a metallic alkaline earth metal with the symbol Ba, and atomic number 56. It never occurs in nature in its pure form due to its reactivity with air, but combines with other chemicals such as sulfur or carbon and oxygen to form barium compounds that may be found as minerals. Bromine is a halogen element with the symbol Br and atomic number 35. Diatomic bromine does not occur naturally, but bromine salts can be found in crustal rock. (L625, L214, 408, L201)