{"id":605,"date":"2011-05-23T08:46:52","date_gmt":"2011-05-22T20:46:52","guid":{"rendered":"https:\/\/blogs.otago.ac.nz\/ouassa\/?p=605"},"modified":"2011-05-23T08:54:08","modified_gmt":"2011-05-22T20:54:08","slug":"equilibrium","status":"publish","type":"post","link":"https:\/\/blogs.otago.ac.nz\/ouassa\/equilibrium\/","title":{"rendered":"Equilibrium"},"content":{"rendered":"<p>This achievement standard involves describing properties of aqueous systems using equilibrium principles.<\/p>\n<p style=\"margin-bottom: 0cm\"><strong>Aqueous systems<\/strong> are limited to those in which proton transfer occurs and those involving a sparingly soluble ionic solid.<\/p>\n<p><strong>Properties<\/strong> of aqueous systems are related to the  nature and the concentration of the species present in the solution.  Description, explanation and application, or discussion of these  properties may be qualitative and\/or quantitative.<\/p>\n<p><strong>Qualitative evidence may include<\/strong><\/p>\n<ul>\n<li>correlation between acid or base strength, <em>K<\/em><sub>a<\/sub> and pH<\/li>\n<li>relative equilibrium concentrations of dissolved species<\/li>\n<li>variability in solubility of a sparingly soluble salt due to the  formation of a complex ion, the addition of a common ion, or the  reaction of a basic anion with added acid<\/li>\n<li>features of titration curves including buffer region, equivalence  point and selection of indicator (titrations of weak acids with weak  bases are excluded)<\/li>\n<li>the nature of buffer solutions.<\/li>\n<\/ul>\n<p><strong>Quantitative evidence includes calculations involving<\/strong><\/p>\n<ul>\n<li><em>K<\/em><sub>a<\/sub><em>, K<\/em><sub>w<\/sub><em> <\/em>and pH limited to\n<ul>\n<li>solutions of bases, monoprotic acids and buffers<\/li>\n<li>those in which the extent of reaction is small so that the  equilibrium concentration of a dissolved weak acid can be approximated  by the initial concentration, ie [HA] = <em>c<\/em>(HA)<\/li>\n<li>pH at a particular point in a titration;<\/li>\n<\/ul>\n<\/li>\n<li><em>K<\/em><sub>s<\/sub> and solubility limited to\n<ul>\n<li>AB, A<sub>2<\/sub>B and AB<sub>2<\/sub> type solids where neither of the ions A or B react further with water<\/li>\n<li>calculating the concentration of one ion given the other<\/li>\n<li>calculating the solubility in water and in solutions already containing one of the ions A or B (a common ion)<\/li>\n<li>predicting precipitation or dissolution.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>This achievement standard involves describing properties of aqueous systems using equilibrium principles. Aqueous systems are limited to those in which proton transfer occurs and those involving a sparingly soluble ionic solid. Properties of aqueous systems are related to the nature &hellip; <a href=\"https:\/\/blogs.otago.ac.nz\/ouassa\/equilibrium\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":5720,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[482,489],"tags":[46392,505],"class_list":["post-605","post","type-post","status-publish","format-standard","hentry","category-chemistry-resources","category-equilibrium","tag-chemistry-resources","tag-curriculum"],"_links":{"self":[{"href":"https:\/\/blogs.otago.ac.nz\/ouassa\/wp-json\/wp\/v2\/posts\/605","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.otago.ac.nz\/ouassa\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.otago.ac.nz\/ouassa\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.otago.ac.nz\/ouassa\/wp-json\/wp\/v2\/users\/5720"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.otago.ac.nz\/ouassa\/wp-json\/wp\/v2\/comments?post=605"}],"version-history":[{"count":0,"href":"https:\/\/blogs.otago.ac.nz\/ouassa\/wp-json\/wp\/v2\/posts\/605\/revisions"}],"wp:attachment":[{"href":"https:\/\/blogs.otago.ac.nz\/ouassa\/wp-json\/wp\/v2\/media?parent=605"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.otago.ac.nz\/ouassa\/wp-json\/wp\/v2\/categories?post=605"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.otago.ac.nz\/ouassa\/wp-json\/wp\/v2\/tags?post=605"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}