Editing Halide (section)

{{Short description|Chemical compound composed of a halogen atom and some other element}}
{{otheruses}}
{{See also|Organic halide}}
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[[File:Atomic & ionic radii halides.svg|Radii in picometers of common halogen atoms (gray/black) and the corresponding halide anions (blue)|right|thumb|120px]]
In [[chemistry]], a '''halide''' (rarely '''halogenide'''<ref>{{Cite web|title=Definition of HALOGENIDE|url=https://www.merriam-webster.com/dictionary/halogenide|access-date=2022-01-07|website=www.merriam-webster.com|language=en}}</ref>) is a [[Binary phase|binary chemical 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]] (or more electropositive) than the halogen, to make a [[fluoride]], [[chloride]], [[bromide]], [[iodide]], [[astatide]], or theoretically [[tennesside]] compound. The [[alkali metals]] combine directly with halogens under appropriate conditions forming halides of the general formula, MX (X = F, Cl, Br or I). Many [[salt (chemistry)|salt]]s are halides; the ''hal-'' syllable in ''halide'' and ''[[halite]]'' reflects [[Halogen#Etymology|this correlation]].<ref>{{Greenwood&Earnshaw2nd| page = 82}}</ref>

A '''halide ion''' is a halogen atom bearing a negative charge. The common halide [[anion]]s are [[fluoride]] ({{chem2|F-}}), [[chloride]] ({{chem2|Cl-}}), [[bromide]] ({{chem2|Br-}}), and [[iodide]] ({{chem2|I-}}). Such ions are present in many [[ionic bonding|ionic]] halide salts. [[Halide mineral]]s contain halides. All these halide anions are colorless.  Halides also form covalent bonds, examples being colorless [[titanium tetrafluoride|TiF<sub>4</sub>]], colorless [[titanium tetrachloride|TiCl<sub>4</sub>]], orange [[titanium tetrabromide|TiBr<sub>4</sub>]], and brown [[titanium tetraiodide|TiI<sub>4</sub>]].  The heavier members TiCl<sub>4</sub>, TiBr<sub>4</sub>, TiI<sub>4</sub> can be distilled readily because they are molecular. The outlier is TiF<sub>4</sub>, [[melting point|m.p. 284 °C]], because it has a polymeric structure.  Fluorides often differ from the heavier halides.<ref>{{Greenwood&Earnshaw2nd| page = 694}}</ref>