CaBr2

Calcium bromide is an inorganic compound with the formula CaBr2. It appears as a white, crystalline solid that is highly soluble in water. The solid is hygroscopic and deliquescent, and in aqueous solution it dissociates into Ca2+ and 2 Br- ions.

In solution and use, CaBr2 serves as a source of bromide ions in various applications. The compound is mainly used industrially for dense brine solutions, and calcium bromide brines are employed in oil and gas drilling and completion fluids to provide hydrostatic pressure. It also finds use as a laboratory source of bromide in chemical synthesis and related processes. CaBr2 can be prepared by reactions of hydrobromic acid with calcium-containing bases or carbonates, for example CaCO3 + 2 HBr → CaBr2 + CO2 + H2O, and by salt metathesis routes such as CaCl2 + 2 NaBr → CaBr2 + 2 NaCl.

Occurrence and production methods reflect its status as a soluble salt rather than a common mineral. Natural deposits of calcium bromide are not as widely reported as other halide minerals, so most CaBr2 is produced industrially from bromide-containing reagents.

Safety and handling considerations are important: calcium bromide can be irritating to skin and eyes, and bromide salts can cause adverse effects if ingested or inhaled in significant quantities. Prolonged exposure or high-dose exposure may lead to bromide-related toxicity. It should be stored in a dry, well-ventilated area in tightly closed containers, away from incompatible materials.