{"id":229530,"date":"2025-06-08T09:08:50","date_gmt":"2025-06-08T09:08:50","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=229530"},"modified":"2025-06-08T09:08:52","modified_gmt":"2025-06-08T09:08:52","slug":"lead-ii-chromate-pbcro4-is-a-slightly-soluble-salt","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/06\/08\/lead-ii-chromate-pbcro4-is-a-slightly-soluble-salt\/","title":{"rendered":"Lead (II) chromate, PbCrO4, is a slightly soluble salt."},"content":{"rendered":"\n<p>Lead (II) chromate, PbCrO4, is a slightly soluble salt. Write a net ionic equation for the dissolution of solid PbCrO4 in water. Write an equilibrium constant expression for this reaction. K = What might one add to increase the solubility of the PbCrO4? Write equations to describe how this added reagent works to increase the PbCrO4 solubility. What reagent could be added to decrease the concentration of Pb2+ in solution<\/p>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-1-color\">The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Net Ionic Equation and Equilibrium Expression<\/h3>\n\n\n\n<p>Lead(II) chromate (PbCrO4\\text{PbCrO}_4PbCrO4\u200b) is a slightly soluble salt, and its dissolution in water can be represented by the following <strong>net ionic equation<\/strong>: PbCrO4(s)\u21ccPb2+(aq)+CrO42\u2212(aq)\\text{PbCrO}_4(s) \\rightleftharpoons \\text{Pb}^{2+}(aq) + \\text{CrO}_4^{2-}(aq)PbCrO4\u200b(s)\u21ccPb2+(aq)+CrO42\u2212\u200b(aq)<\/p>\n\n\n\n<p>The corresponding <strong>equilibrium constant expression<\/strong>, known as the <strong>solubility product (Ksp_\\text{sp}sp\u200b)<\/strong>, is: Ksp=[Pb2+][CrO42\u2212]K_{sp} = [\\text{Pb}^{2+}][\\text{CrO}_4^{2-}]Ksp\u200b=[Pb2+][CrO42\u2212\u200b]<\/p>\n\n\n\n<p>This expression quantifies how much PbCrO4\\text{PbCrO}_4PbCrO4\u200b dissolves in water at equilibrium.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Increasing Solubility of PbCrO\u2084<\/h3>\n\n\n\n<p>To <strong>increase the solubility<\/strong> of PbCrO4\\text{PbCrO}_4PbCrO4\u200b, one can <strong>add a substance that removes either Pb2+\\text{Pb}^{2+}Pb2+ or CrO42\u2212\\text{CrO}_4^{2-}CrO42\u2212\u200b from solution<\/strong>, thereby shifting the equilibrium to the right (according to Le Ch\u00e2telier\u2019s Principle).<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">Example: Adding Hydrochloric Acid (HCl)<\/h4>\n\n\n\n<p>Adding HCl introduces H+\\text{H}^+H+ ions, which react with CrO42\u2212\\text{CrO}_4^{2-}CrO42\u2212\u200b to form HCrO4\u2212\\text{HCrO}_4^-HCrO4\u2212\u200b: CrO42\u2212(aq)+H+(aq)\u21ccHCrO4\u2212(aq)\\text{CrO}_4^{2-}(aq) + \\text{H}^+(aq) \\rightleftharpoons \\text{HCrO}_4^-(aq)CrO42\u2212\u200b(aq)+H+(aq)\u21ccHCrO4\u2212\u200b(aq)<\/p>\n\n\n\n<p>This reaction decreases the concentration of CrO42\u2212\\text{CrO}_4^{2-}CrO42\u2212\u200b, driving the dissolution equilibrium to the right and increasing the solubility of PbCrO4\\text{PbCrO}_4PbCrO4\u200b.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Decreasing Pb\u00b2\u207a Concentration<\/h3>\n\n\n\n<p>To <strong>decrease the concentration of Pb2+\\text{Pb}^{2+}Pb2+<\/strong> in solution, a reagent that forms an insoluble compound with lead can be added.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">Example: Adding Sodium Sulfate (Na\u2082SO\u2084)<\/h4>\n\n\n\n<p>Sulfate ions react with lead(II) ions to form insoluble lead(II) sulfate: Pb2+(aq)+SO42\u2212(aq)\u2192PbSO4(s)\\text{Pb}^{2+}(aq) + \\text{SO}_4^{2-}(aq) \\rightarrow \\text{PbSO}_4(s)Pb2+(aq)+SO42\u2212\u200b(aq)\u2192PbSO4\u200b(s)<\/p>\n\n\n\n<p>This reaction removes Pb2+\\text{Pb}^{2+}Pb2+ from solution by forming a precipitate, lowering its concentration.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Summary<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Dissolution reaction<\/strong>: PbCrO4(s)\u21ccPb2+(aq)+CrO42\u2212(aq)\\text{PbCrO}_4(s) \\rightleftharpoons \\text{Pb}^{2+}(aq) + \\text{CrO}_4^{2-}(aq)PbCrO4\u200b(s)\u21ccPb2+(aq)+CrO42\u2212\u200b(aq)<\/li>\n\n\n\n<li><strong>Equilibrium<\/strong>: Ksp=[Pb2+][CrO42\u2212]K_{sp} = [\\text{Pb}^{2+}][\\text{CrO}_4^{2-}]Ksp\u200b=[Pb2+][CrO42\u2212\u200b]<\/li>\n\n\n\n<li><strong>To increase solubility<\/strong>: Add HCl (removes CrO42\u2212\\text{CrO}_4^{2-}CrO42\u2212\u200b)<\/li>\n\n\n\n<li><strong>To decrease Pb2+\\text{Pb}^{2+}Pb2+<\/strong>: Add Na\u2082SO\u2084 (forms PbSO4\\text{PbSO}_4PbSO4\u200b precipitate)<\/li>\n<\/ul>\n\n\n\n<p>These strategies exploit chemical equilibria to control solubility and ion concentrations in solution<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/06\/learnexams-banner5-153.jpeg\" alt=\"\" class=\"wp-image-229531\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Lead (II) chromate, PbCrO4, is a slightly soluble salt. Write a net ionic equation for the dissolution of solid PbCrO4 in water. Write an equilibrium constant expression for this reaction. K = What might one add to increase the solubility of the PbCrO4? Write equations to describe how this added reagent works to increase the [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-229530","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/229530","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=229530"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/229530\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=229530"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=229530"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=229530"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}