Gold chalcogenides 145714 198139800 2008-03-14T06:35:08Z 75.47.204.159 '''Gold chalcogenides''' are compounds formed between [[gold]] and one of the [[chalcogen]]s, elements from [[group 16]] of the [[periodic table]]: [[oxygen]], [[sulfur]], [[selenium]] or [[tellurium]]. *Gold(III) oxide, Au<sub>2</sub>O<sub>3</sub>. decomposes into gold and oxygen above 160&nbsp;°C. dissolves in concentrated alkalis to form solutions which probably contain the [Au(OH)<sub>4</sub>]<sup>&minus;</sup> ion *Gold(I) sulfide, Au<sub>2</sub>S. formed by passing [[hydrogen sulfide]] through solutions of gold(I) compounds *Gold(III) sulfide, Au<sub>2</sub>S<sub>3</sub>. unstable in the presence of water *Gold tellurides: Au<sub>2</sub>Te<sub>3</sub>, Au<sub>3</sub>Te<sub>5</sub> and AuTe<sub>2</sub> are known as [[non-stoichiometric compound]]s. they show [[metallic conductivity]]. Au<sub>3</sub>Te<sub>5</sub> is a [[superconductor]] at very low temperatures. ==References== {{Greenwood&Earnshaw}} [[Category:Gold compounds]] [[Category:Oxides]] [[Category:Sulfides]] [[Category:Tellurides]] {{inorganic-compound-stub}} [[nl:Goudchalcogeniden]]