Halogenides

Halogenides are chemical compounds that contain halogen elements—fluorine, chlorine, bromine, iodine, and astatine. The term covers both inorganic salts that contain halide ions and organic compounds in which a halogen atom is bonded to carbon. The halide ion X− is the reduced form of a halogen.

Inorganic halides include metal salts such as sodium chloride (NaCl), potassium bromide (KBr), and calcium fluoride (CaF2), as well as hydrogen halides (HF, HCl, HBr, HI) when dissolved in water forming hydrohalic acids. Many inorganic halides are soluble in water, though some heavier metal halides have limited solubility.

Organic halides, or haloalkanes and aryl halides, feature halogen atoms bonded to carbon. They arise from substitution or addition reactions and are important intermediates in organic synthesis. The carbon–halogen bond strength and reactivity vary by halogen and substitution pattern, with C–I bonds typically weaker and more reactive than C–F bonds.

Properties and applications: Halogenides are broadly used in chemistry and industry. Sodium chloride is essential in food, while hydrogen halides influence acidity and processing. Silver halides are central to traditional photography. Organic halides serve as solvents, refrigerants, pharmaceuticals, and synthetic intermediates. Safety considerations include toxicity and environmental persistence, especially for certain organohalogen compounds.

See also: Halide, Halogen, Interhalogen compounds, Organohalide.