Deutsch: Halogene / Español: Halógeno / Português: Halogénio / Français: Halogène / Italiano: Alogeni
A halogen is a member of the chemical group of halogens. It is the only periodic table group that contains elements in all three familiar states of matter at standard temperature and pressure. All of the halogens form acids when bonded to hydrogen. Most halogens are typically produced from minerals of salts. The middle halogens, that is, chlorine, bromine and iodine, are often used as disinfectants. The halogens are also all toxic.
In an industrial or industry context, halogens are chemical elements such as fluorine, chlorine, bromine, and iodine, that are used in a variety of applications, including as components of lighting, refrigerants, fire-retardants, and disinfectants. For example:
- Fluorescent lamps contain a small amount of mercury vapor and halogens, which increase their efficiency and life span.
- Chlorofluorocarbons (CFCs) are halocarbons that were widely used as refrigerants until they were found to contribute to the depletion of the ozone layer.
- Brominated flame retardants are used to reduce the flammability of plastics, textiles, and electronics.
- Iodine is used as a sterilizing agent in the production of medical equipment and as a component of some food additives.