Halide 239097 217933461 2008-06-08T11:15:02Z Geonarva 2480496 +et A '''halide''' is a [[binary compound]], of which one part is a [[halogen]] [[atom]] and the other part is an [[chemical element|element]] or [[radical (chemistry)|radical]] that is less [[electronegative]] than the halogen, to make a [[fluoride]], [[chloride]], [[bromide]], [[iodide]], or [[astatide]] compound. Many [[salt (chemistry)|salt]]s are halides. All Group 1 metals form halides with the halogens and they are white solids. A '''halide ion''' is a halogen atom bearing a negative charge. The halide [[anion]]s are [[fluoride]] (F<sup>−</sup>), [[chloride]] (Cl<sup>−</sup>), [[bromide]] (Br<sup>−</sup>), [[iodide]] (I<sup>−</sup>) and [[astatide]] (At<sup>−</sup>). Such ions are present in all [[ionic bonding|ionic]] halide salts. ==Halides in organic chemistry== In [[organic chemistry]] halides represent a [[functional group]]. Any organic compound that contains a halogen atom can be considered a halide. [[Alkyl halide]]s are organic compounds of the type R-X, containing an [[alkyl]] group R [[covalent]]ly bonded to a halogen X. '''Pseudohalides''' resemble halides in their charge and reactivity; common examples are [[azide]]s NNN-, [[isocyanate]] -NCO, [[Isocyanide]], CN-, etc.<ref>{{GoldBookRef | title = pseudohalide | file = P04930 | year = 1995}}</ref> A [[chemical test]] for the detection of halogen in chemical substances is the [[Carius halogen method]]. '''Dihalides''' are commonly used in the synthesis of cyclic alkanes. == Test for Halide ions == Halide compounds such as KCl, KBr and KI can be tested with silver nitrate solution, AgNO<sub>3</sub>. The halogen will react with Ag<sup>+</sup> and form a [[precipitate]], with colour as follow:<br /> [[AgF]] - Yellowish Brown<br /> [[AgCl]] - White<br /> [[AgBr]] - Creamy (Pale Yellow)<br /> [[AgI]] - Yellow == Halides in lighting == [[:Category:Metal halides|Metal halides]] are used in [[high-intensity discharge lamp]]s called [[metal halide lamp]]s, such as those used in modern [[street light]]s. These are more [[energy efficiency|energy-efficient]] than [[mercury-vapor lamp]]s, and have much better [[colour]] [[rendition]] than [[orange (colour)|orange]] [[Sodium-vapor lamp|high-pressure sodium lamps]]. Metal halide lamps are also commonly used in greenhouses or in rainy climates to supplement natural sunlight. HID (High-intensity discharge) lamps however, contribute highly to [[light pollution]]. Sodium-vapor are favored for this reason. ==Halide compounds== Examples of halide compounds are: * [[sodium chloride]] (NaCl) * [[potassium chloride]] (KCl) * [[potassium iodide]] (KI) * [[lithium chloride]] (LiCl) * [[copper(II) chloride]] (CuCl<sub>2</sub>) * [[chlorine fluoride]] (ClF) * [[Bromomethane]] (CH<sub>3</sub>Br) * [[Iodoform]] (CHI<sub>3</sub>) * [[silver chloride]] (AgCl) ==See also== *[[Salinity]] *[[Functional groups]] ==References== <references/> [[Category:functional groups]] [[Category:Salts]] [[Category:Halides|*]] [[bs:Halidi]] [[ca:Halur]] [[da:Halogenid]] [[de:Halogenide]] [[et:Halogeniid]] [[es:Haluro]] [[eo:Halogenido]] [[eu:Haluro]] [[fr:Halogénure]] [[it:Alogenuro]] [[mk:Халид]] [[nl:Halogeniden]] [[ja:ハロゲン化合物]] [[pl:Halogenki]] [[ru:Галогенид]] [[sk:Halogenid]] [[fi:Halidi]] [[sv:Halogenider]] [[zh:卤化物]]