{"id":33182,"date":"2021-02-13T14:25:27","date_gmt":"2021-02-13T14:25:27","guid":{"rendered":"https:\/\/gkscientist.com\/?p=33182"},"modified":"2022-07-29T09:51:44","modified_gmt":"2022-07-29T09:51:44","slug":"werner-theory-of-coordination-compounds","status":"publish","type":"post","link":"https:\/\/gkscientist.com\/werner-theory-of-coordination-compounds\/","title":{"rendered":"Werner Theory of Coordination Compounds"},"content":{"rendered":"\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_65 counter-hierarchy ez-toc-counter ez-toc-light-blue ez-toc-container-direction\">\n<p class=\"ez-toc-title\">Table of Contents<\/p>\n<label for=\"ez-toc-cssicon-toggle-item-662ca4b4d75a4\" class=\"ez-toc-cssicon-toggle-label\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input type=\"checkbox\"  id=\"ez-toc-cssicon-toggle-item-662ca4b4d75a4\"  aria-label=\"Toggle\" \/><nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/gkscientist.com\/werner-theory-of-coordination-compounds\/#Werner_Theory_of_Coordination_Compounds\" title=\"Werner Theory of Coordination Compounds:\">Werner Theory of Coordination Compounds:<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/gkscientist.com\/werner-theory-of-coordination-compounds\/#Disadvantages_of_Werners_Coordination_Theory\" title=\"Disadvantages of  Werner&#8217;s Coordination Theory:\">Disadvantages of  Werner&#8217;s Coordination Theory:<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/gkscientist.com\/werner-theory-of-coordination-compounds\/#Types_of_Hybridizations_and_Geometries_in_Coordination_Complexes\" title=\"Types of Hybridizations and Geometries in Coordination Complexes:\">Types of Hybridizations and Geometries in Coordination Complexes:<\/a><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Werner_Theory_of_Coordination_Compounds\"><\/span>Werner Theory of Coordination Compounds:<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p><strong>Alfred Werner<\/strong> in <strong>1893 <\/strong>proposed the first most successful theory to explain the formation and properties of coordination or complex compounds in terms of their structures known as <strong>Werner&#8217;s Coordination Theory<\/strong> and he was awarded Nobel Prize in chemistry for his theory. <\/p>\n\n\n\n<p><strong>The salient features of this theory are as follows-<\/strong><\/p>\n\n\n\n<p><strong>(i)<\/strong> Metals have two types of valencies (or linkages) known as- <strong>(a)<\/strong> Primary or Principal or Ionisable Valency and <strong>(b)<\/strong> Secondary or Auxiliary or Non-ionisable Valency.<\/p>\n\n\n\n<p><strong>(ii)<\/strong> In modern terminology, the primary valencies usually indicate the oxidation number of the metal ion whereas secondary valencies represent the coordination number of the metal.<\/p>\n\n\n\n<p><strong>(iii)<\/strong> The primary valency of the central metal ion is always satisfied by anions and its attachment to the metal is shown by dotted lines. The secondary valencies may be satisfied either by anions or by neutral molecules and their attachment to the metal is shown by thick lines. <strong>For example- <\/strong>NH<sub>3<\/sub> is added to cobalt chloride, a complex CoCl<sub>3<\/sub>.6NH<sub>3<\/sub> is obtained, in which primary valencies of Co are satisfied by three chloride ions whereas the secondary valencies are satisfied by six NH<sub>3<\/sub> molecules.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large wp-duotone-0693e3-ffffff-1\"><img loading=\"lazy\" decoding=\"async\" width=\"365\" height=\"204\" src=\"https:\/\/i0.wp.com\/gkscientist.com\/wp-content\/uploads\/2021\/02\/cobalt-chloride-with-ammonia-six-atoms.png?resize=365%2C204&#038;ssl=1\" alt=\"cobalt chloride with ammonia-six atoms\" class=\"wp-image-33220\" title=\"\" srcset=\"https:\/\/i0.wp.com\/gkscientist.com\/wp-content\/uploads\/2021\/02\/cobalt-chloride-with-ammonia-six-atoms.png?w=365&amp;ssl=1 365w, https:\/\/i0.wp.com\/gkscientist.com\/wp-content\/uploads\/2021\/02\/cobalt-chloride-with-ammonia-six-atoms.png?resize=300%2C168&amp;ssl=1 300w\" sizes=\"(max-width: 365px) 100vw, 365px\" data-recalc-dims=\"1\" \/><\/figure><\/div>\n\n\n<p><strong>(iv)<\/strong> The secondary valencies from the coordination sphere of the complex and are always shown is square brackets and they do not ionise in solution to give constituent ions of the complex ion.<\/p>\n\n\n\n<p><strong>(v)<\/strong> Every metal has a fixed number of secondary valencies and it must satisfy all its primary and secondary valencies. In order to fulfil this requirement, an anion may perform dual behaviour of satisfying both the Primary and Secondary valencies and their attachment is shown both by dotted as well as thick lines. Such valencies which perform a dual role are not ionised. <strong>For example- <\/strong>the complex like CoCl<sub>3<\/sub>.5NH<sub>3<\/sub>, CoCl<sub>3<\/sub>.4NH<sub>3<\/sub>, CoCl<sub>3<\/sub>.3NH<sub>3<\/sub> are represented with complex species shown within the square brackets (coordination sphere) and ionisation ligands (primary valency) kept outside the sphere i.e.<\/p>\n\n\n\n<figure class=\"wp-block-table is-style-stripes\"><table><thead><tr><th>S.No.<\/th><th><strong>Werner Formula<\/strong><\/th><th><strong>No. of ions<\/strong><\/th><th><strong>Modern Formula<\/strong><\/th><\/tr><\/thead><tbody><tr><td>(i)<\/td><td>CoCl<sub>3<\/sub>.5NH<sub>3<\/sub><\/td><td>3<\/td><td>[Co(NH<sub>3<\/sub>)<sub>5<\/sub>Cl]Cl<sub>2<\/sub><\/td><\/tr><tr><td>(ii)<\/td><td>CoCl<sub>3<\/sub>.4NH<sub>3<\/sub><\/td><td>2<\/td><td>[Co(NH<sub>3<\/sub>)<sub>4<\/sub>Cl<sub>2<\/sub>]Cl<\/td><\/tr><tr><td>(iii)<\/td><td>CoCl<sub>3<\/sub>.3NH<sub>3<\/sub><\/td><td>0<\/td><td>[Co(NH<sub>3<\/sub>)<sub>3<\/sub>Cl<sub>3<\/sub>]<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large wp-duotone-0693e3-ffffff-2\"><img loading=\"lazy\" decoding=\"async\" width=\"730\" height=\"195\" src=\"https:\/\/i0.wp.com\/gkscientist.com\/wp-content\/uploads\/2021\/02\/werner-and-modern-formula-structure.png?resize=730%2C195&#038;ssl=1\" alt=\"werner and modern formula structure\" class=\"wp-image-33223\" title=\"\" srcset=\"https:\/\/i0.wp.com\/gkscientist.com\/wp-content\/uploads\/2021\/02\/werner-and-modern-formula-structure.png?w=800&amp;ssl=1 800w, https:\/\/i0.wp.com\/gkscientist.com\/wp-content\/uploads\/2021\/02\/werner-and-modern-formula-structure.png?resize=300%2C80&amp;ssl=1 300w, https:\/\/i0.wp.com\/gkscientist.com\/wp-content\/uploads\/2021\/02\/werner-and-modern-formula-structure.png?resize=768%2C205&amp;ssl=1 768w\" sizes=\"(max-width: 730px) 100vw, 730px\" data-recalc-dims=\"1\" \/><\/figure><\/div>\n\n\n<p><strong>(vi)<\/strong> The primary valencies are non-directional whereas the ligands satisfying the secondary valencies are always directed towards fixed positions in space giving rise to<strong> stereo-isomerism<\/strong> in complex compounds. These coordinated groups arrange themselves around the metal ion in a planar, tetrahedral or octahedral manner depending upon the coordination number of the metal ion. For example- when the coordination number is <strong>4<\/strong>, the arrangement is either square planar or tetrahedral while it is octahedral when the coordination number is <strong>6<\/strong>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Disadvantages_of_Werners_Coordination_Theory\"><\/span>Disadvantages of  Werner&#8217;s Coordination Theory:<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<ul><li>There is no theoretical explanation for bonding because electrons and noble gases which form the bases for bonding are not known at that time.<\/li><li>This theory does not explain the various facts like colour, magnetic behaviour etc.<\/li><li>This theory does not explain why certain elements form coordination compounds and not others.<\/li><li>It does not explain why the coordination sphere has a definite geometry.<\/li><li>It does not explain the optical properties of compounds.<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Types_of_Hybridizations_and_Geometries_in_Coordination_Complexes\"><\/span>Types of Hybridizations and Geometries in Coordination Complexes:<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<figure class=\"wp-block-table is-style-stripes\"><table class=\"has-fixed-layout\"><thead><tr><th>Hybridization<\/th><th>Geometry<\/th><\/tr><\/thead><tbody><tr><td>sp<sup>3<\/sup><\/td><td>Tetrahedral<\/td><\/tr><tr><td>dsp<sup>2<\/sup><\/td><td>Square Planar<\/td><\/tr><tr><td>sp<sup>3<\/sup>d<sup>2<\/sup> or d<sup>2<\/sup>sp<sup>3<\/sup><\/td><td>Octahedral<\/td><\/tr><tr><td>dsp<sup>3<\/sup><\/td><td>Trigonal Bipyramidal<\/td><\/tr><tr><td>sp<sup>3<\/sup>d<\/td><td>Square Pyramidal<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<figure class=\"wp-block-embed aligncenter is-type-wp-embed is-provider-gk-scientist wp-block-embed-gk-scientist\"><div class=\"wp-block-embed__wrapper\">\n<blockquote class=\"wp-embedded-content\" data-secret=\"HxMBu9xn3H\"><a href=\"https:\/\/gkscientist.com\/molecular-orbital-theory\/\">Molecular Orbital Theory<\/a><\/blockquote><iframe class=\"wp-embedded-content\" sandbox=\"allow-scripts\" security=\"restricted\" style=\"position: absolute; clip: rect(1px, 1px, 1px, 1px);\" title=\"&#8220;Molecular Orbital Theory&#8221; &#8212; GK SCIENTIST\" src=\"https:\/\/gkscientist.com\/molecular-orbital-theory\/embed\/#?secret=PMlZvp35HY#?secret=HxMBu9xn3H\" data-secret=\"HxMBu9xn3H\" width=\"600\" height=\"338\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe>\n<\/div><\/figure>\n\n\n\n<hr class=\"wp-block-separator aligncenter has-alpha-channel-opacity is-style-wide\"\/>\n\n\n\n<ul><li><a aria-label=\" (opens in a new tab)\" href=\"https:\/\/gkscientist.com\/de-broglie-hypothesis-and-de-broglie-equation\/\" target=\"_blank\" rel=\"noreferrer noopener\" class=\"rank-math-link\">de-Broglie Hypothesis (Dual Nature of Matter)<\/a><\/li><li><a aria-label=\" (opens in a new tab)\" href=\"https:\/\/gkscientist.com\/uses-of-alkanes-alkenes-and-alkynes\/\" target=\"_blank\" rel=\"noreferrer noopener\" class=\"rank-math-link\">Uses of Alkanes Alkenes and Alkynes<\/a><\/li><li><a aria-label=\" (opens in a new tab)\" href=\"https:\/\/gkscientist.com\/radioactive-disintegration-series\/\" target=\"_blank\" rel=\"noreferrer noopener\" class=\"rank-math-link\">Radioactive Disintegration Series<\/a><\/li><li><a href=\"https:\/\/gkscientist.com\/oxidation-and-reduction\/\" target=\"_blank\" aria-label=\" (opens in a new tab)\" rel=\"noreferrer noopener\" class=\"rank-math-link\">Oxidation and Reduction<\/a><\/li><li><a href=\"https:\/\/gkscientist.com\/valence-electrons-and-isotopes\/\" target=\"_blank\" aria-label=\" (opens in a new tab)\" rel=\"noreferrer noopener\" class=\"rank-math-link\">Valence Electrons and Isotopes<\/a><\/li><li><a rel=\"noreferrer noopener\" class=\"rank-math-link\" href=\"https:\/\/drive.google.com\/file\/d\/1qDotmoHGe0JGBj3K9kyl25UKvSWZhDwv\/view?usp=sharing\" target=\"_blank\">Atoms, Molecules and Chemical Arithmetic<\/a>\u2013 NIOS<\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Werner Theory of Coordination Compounds: Alfred Werner in 1893 proposed the first most successful theory to explain the formation and properties of coordination or complex compounds in terms of their structures known as Werner&#8217;s Coordination Theory and he was awarded Nobel Prize in chemistry for his theory. The salient features of this theory are as follows- (i) Metals have two types of valencies (or linkages) known as- (a) Primary or Principal or Ionisable Valency and (b) Secondary or Auxiliary or Non-ionisable Valency. (ii) In modern terminology, the primary valencies usually indicate the oxidation number of the metal ion whereas secondary <\/p>\n","protected":false},"author":1,"featured_media":33215,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[5896],"tags":[2878,6951,1397,1395,2877],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"https:\/\/i0.wp.com\/gkscientist.com\/wp-content\/uploads\/2021\/02\/Werners-Coordination-Theory.jpg?fit=350%2C270&ssl=1","_links":{"self":[{"href":"https:\/\/gkscientist.com\/wp-json\/wp\/v2\/posts\/33182"}],"collection":[{"href":"https:\/\/gkscientist.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gkscientist.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gkscientist.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/gkscientist.com\/wp-json\/wp\/v2\/comments?post=33182"}],"version-history":[{"count":0,"href":"https:\/\/gkscientist.com\/wp-json\/wp\/v2\/posts\/33182\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/gkscientist.com\/wp-json\/wp\/v2\/media\/33215"}],"wp:attachment":[{"href":"https:\/\/gkscientist.com\/wp-json\/wp\/v2\/media?parent=33182"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gkscientist.com\/wp-json\/wp\/v2\/categories?post=33182"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gkscientist.com\/wp-json\/wp\/v2\/tags?post=33182"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}