Editing Antimony (section)

==Compounds==
{{See also|Category:Antimony compounds}}
Antimony compounds are often classified according to their oxidation state: Sb(III) and Sb(V). The +5 [[oxidation state]] is more common.<ref>[[#Greenwood|Greenwood and Earnshaw]], p. 553</ref>

===Oxides and hydroxides===
[[Antimony trioxide]] is formed when antimony is burnt in air.<ref name="reger2009">{{cite book|title=Chemistry: Principles and Practice|author=Reger, Daniel L.|author2=Goode, Scott R.|author3=Ball, David W.|name-list-style=amp|edition=3rd|url=https://books.google.com/books?id=OUIaM1V3ThsC&pg=PA883|publisher=Cengage Learning|date=2009|isbn=978-0-534-42012-3|page=883}}</ref> In the gas phase, the molecule of the compound is {{chem2|Sb4O6}}, but it polymerizes upon condensing.<ref name=w758/> [[Antimony pentoxide]] ({{chem2|Sb4O10}}) can be formed only by oxidation with concentrated [[nitric acid]].<ref name="house">{{cite book|title=Inorganic chemistry|publisher=Academic Press|author=House, James E.|url=https://books.google.com/books?id=ocKWuxOur-kC&pg=PA502|date=2008|isbn=978-0-12-356786-4|page=502}}</ref> Antimony also forms a mixed-valence oxide, [[antimony tetroxide]] ({{chem2|Sb2O4}}), which features both Sb(III) and Sb(V).<ref name="house" /> Unlike oxides of [[phosphorus]] and [[arsenic]], these oxides are [[amphoteric]], do not form well-defined [[oxoacid]]s, and react with acids to form antimony salts.

Antimonous acid {{chem2|Sb(OH)3}} is unknown, but the conjugate base sodium antimonite ({{chem2|[Na3SbO3]4}}) forms upon fusing [[sodium oxide]] and {{chem2|Sb4O6}}.<ref>[[#Wiberg|Wiberg and Holleman]], p. 763</ref> Transition metal antimonites are also known.<ref name="norman">{{cite book|title=Chemistry of arsenic, antimony, and bismuth|author=Godfrey, S. M.|author2=McAuliffe, C. A.|author3=Mackie, A. G.|author4=Pritchard, R. G.|name-list-style=amp|editor-last=Norman|editor-first=Nicholas&nbsp;C.|publisher=Springer|date=1998|isbn=978-0-7514-0389-3|ref={{harvid|Norman|1998}}}}</ref>{{rp|122}} Antimonic acid exists only as the hydrate {{chem2|HSb(OH)6}}, forming salts as the antimonate anion {{chem2|Sb(OH)6-}}. When a solution containing this anion is dehydrated, the precipitate contains mixed oxides.<ref name="norman" />{{rp|143}}

The most important antimony ore is [[stibnite]] ({{chem2|Sb2S3}}). Other sulfide minerals include [[pyrargyrite]] ({{chem2|Ag3SbS3}}), [[zinkenite]], [[jamesonite]], and [[boulangerite]].<ref>[[#Wiberg|Wiberg and Holleman]], p. 757</ref> [[Antimony pentasulfide]] is [[non-stoichiometric compound|non-stoichiometric]], which features antimony in the +3 [[oxidation state]] and S–S bonds.<ref>{{cite journal|doi=10.1016/0020-1650(69)80231-X|title=The oxidation number of antimony in antimony pentasulfide|date=1969|last1=Long|first1=G.|journal=Inorganic and Nuclear Chemistry Letters|volume=5|page=21|last2=Stevens|first2=J. G.|last3=Bowen|first3=L. H.|last4=Ruby|first4=S. L.}}</ref> Several thioantimonides are known, such as {{chem2|[Sb6S10](2-)}} and {{chem2|[Sb8S13](2-)}}.<ref>{{cite journal|doi=10.1016/j.jpcs.2006.12.010|title=The synthesis and characterisation of four new antimony sulphides incorporating transition-metal complexes|date=2007|last1=Lees|first1=R.|last2=Powell|first2=A.|last3=Chippindale|first3=A.|journal=Journal of Physics and Chemistry of Solids|volume=68|page=1215|bibcode=2007JPCS...68.1215L|issue=5–6}}</ref>

===Halides===
Antimony forms two series of [[halide]]s: {{chem2|SbX3}} and {{chem2|SbX5}}. The trihalides {{chem2|SbF3|link=antimony trifluoride}}, {{chem2|SbCl3|link=antimony trichloride}}, {{chem2|SbBr3|link=antimony tribromide}}, and {{chem2|SbI3|link=antimony triiodide}} are all molecular compounds having [[trigonal pyramidal molecular geometry]]. The trifluoride is prepared by the reaction of [[antimony trioxide]] with [[hydrofluoric acid]]:<ref>[[#Wiberg|Wiberg and Holleman]], pp. 761–762</ref>
:{{chem2|Sb2O3 + 6 HF -> 2 SbF3 + 3 H2O}}
It is [[Lewis acid]]ic and readily accepts fluoride ions to form the complex anions {{chem2|SbF4-}} and {{chem2|SbF5(2-)}}. Molten antimony trifluoride is a weak [[electrical conductor]]. The trichloride is prepared by dissolving [[stibnite]] in [[hydrochloric acid]]:<ref name="Ullmann" />
:{{chem2|Sb2S3 + 6 HCl -> 2 SbCl3 + 3 H2S}}
Arsenic sulfides are not readily attacked by the hydrochloric acid, so this method offers a route to As-free Sb.

[[File:Antimony-pentafluoride-monomer-3D-balls.png|thumb|upright|left|Structure of gaseous {{chem2|SbF5}}]]
The pentahalides {{chem2|SbF5|link=antimony pentafluoride}} and {{chem2|SbCl5|link=antimony pentachloride}} have [[trigonal bipyramidal molecular geometry]] in the gas phase, but in the liquid phase, {{chem2|SbF5}} is [[polymer]]ic, whereas {{chem2|SbCl5}} is monomeric.<ref>[[#Wiberg|Wiberg and Holleman]], p. 761</ref> Antimony pentafluoride is a powerful Lewis acid used to make the [[superacid]] [[fluoroantimonic acid]] ({{chem2|H2F+*SbF6-}}).

[[Oxohalide|Oxyhalides]] are more common for antimony than for arsenic and phosphorus. [[Antimony trioxide]] dissolves in concentrated acid to form oxoantimonyl compounds such as [[antimony oxychloride|SbOCl]] and {{chem2|(SbO)2SO4}}.<ref>[[#Wiberg|Wiberg and Holleman]], p. 764</ref>

===Antimonides, hydrides, and organoantimony compounds===
Compounds in this class generally are described as derivatives of {{chem2|Sb(3-)}}. Antimony forms [[antimonide]]s with metals, such as [[indium antimonide]] (InSb) and silver antimonide ({{chem2|Ag3Sb}}).<ref>[[#Wiberg|Wiberg and Holleman]], p. 760</ref> The alkali metal and zinc antimonides, such as {{chem2|Na3Sb}} and {{chem2|Zn3Sb2}}, are more reactive. Treating these antimonides with acid produces the highly unstable gas [[stibine]], {{chem2|SbH3}}:<ref>{{cite book|title=Outlines of Chemistry&nbsp;– A Textbook for College Students|author=Kahlenberg, Louis|publisher=READ BOOKS|date=2008|isbn=978-1-4097-6995-8|pages=324–325}}</ref>
:{{chem2|Sb(3-) + 3 H+ -> SbH3}}
Stibine can also be produced by treating {{chem2|Sb(3+)}} salts with hydride reagents such as [[sodium borohydride]]. Stibine decomposes spontaneously at room temperature. Because stibine has a positive [[heat of formation]], it is [[thermodynamic stability|thermodynamically unstable]] and thus antimony does not react with [[hydrogen]] directly.<ref>[[#Greenwood|Greenwood and Earnshaw]], p. 558</ref>

[[Organoantimony chemistry|Organoantimony compounds]] are typically prepared by alkylation of antimony halides with [[Grignard reagent]]s.<ref>Elschenbroich, C. (2006) "Organometallics". Wiley-VCH: Weinheim. {{ISBN|3-527-29390-6}}</ref> A large variety of compounds are known with both Sb(III) and Sb(V) centers, including mixed chloro-organic derivatives, anions, and cations. Examples include [[triphenylstibine]] ({{chem2|Sb(C6H5)3}}) and [[pentaphenylantimony]] ({{chem2|Sb(C6H5)5}}).<ref>[[#Greenwood|Greenwood and Earnshaw]], p. 598</ref>