Barium bromide Barium bromide Barium bromide is the chemical compound with the formula BaBr. Like barium chloride, it dissolves well in water and is toxic in aqueous solution. BaBr crystallizes in a lead chloride motif, giving white orthorhombic crystals which are deliquescent. In aqueous solution BaBr behaves as a simple salt. Barium bromide reacts with the sulfate ion from sulfuric acid to produce a precipitate of barium sulfate. Similar reactions occur with oxalic acid, hydrofluoric acid, and phosphoric acid. Barium bromide can be prepared from barium sulfide or barium carbonate via reaction with hydrobromic acid to give hydrated barium bromide. This happens
Sterling silver Royal Mint in 1843. It bears the royal stamp "ENRI. REX" ("King Henry") but this was added later, in the reign of Henry III. The first legal definition of sterling silver appeared in 1275, when a statute of Edward I specified that 12 Troy ounces of silver for coinage should contain 11 ounces pennyweights of silver and pennyweights of alloy, with 20 pennyweights to the Troy ounce. This is (not precisely) equivalent to a millesimal fineness of 926. In Colonial America, sterling silver was used for currency and general goods as well. Between 1634 and 1776, some 500 silversmiths created