Abstract

Sodium bromide is the most common and available alkali bromide, occurring in both the anhydrous and dihydrate forms. The anhydrous salt is hygroscopic but not deliquescent and has a very high solubility in water. Commercial quantities are prepared from bromine and sodium hydroxide solutions. Sodium bromide is moderately toxic by ingestion and can affect the gastrointestinal and central nervous systems and the skin. A primary use of sodium bromide is as a heavy, clear brine fluid in completing and working over oil and gas wells. Another principal use of sodium bromide is in industrial wastewater treatment. When activated with hypochlorites or isocyanurates sodium bromide becomes a very effective biocide. Sodium bromide is used in the photographic industry, has some application as a cocatalyst, as a wood preservative, and as a pharmaceutical.

Sodium has two fluorides: sodium fluoride, used in pesticide formulations and in the fluoridation of potable water supplies; and sodium bifluoride, used as a laundry sour and in the cleaning of stone and brick building faces. Physical and chemical properties are discussed.

Sodium iodide, its occurrence, physical properties, manufacture, economic aspects, and uses are described. It is produced by acid–base reaction yielding no by-products and is stored on the basic side to retard oxidation.

This important halide salt is used in medicine as a detector for such devices as computer-assisted tomography scans and positron emission tomography. It tends to form the dihydrate at temperatures below 65°C and is deliquescent, which makes it much different in handling characteristics from its potassium counterpart.