Double Replacement Reactions: Precipitation and Ionic Equations<\/h3>\n\n\n\n
In aqueous chemistry, double replacement reactions<\/strong> often lead to the formation of an insoluble compound, or precipitate<\/strong>, which separates out of solution. Let’s analyze two such reactions step-by-step to determine the balanced equations, total and net ionic equations, and identify the spectator ions and the precipitate.<\/p>\n\n\n\n Molecular Equation:<\/strong><\/p>\n\n\n\n FeCl\u2083(aq) + 3NaOH(aq) \u2192 Fe(OH)\u2083(s) + 3NaCl(aq)<\/p>\n\n\n\n Balanced Equation:<\/strong><\/p>\n\n\n\n This equation is already balanced. One Fe\u00b3\u207a ion reacts with three OH\u207b ions to form iron(III) hydroxide, a brown precipitate. Three Na\u207a ions balance the three Cl\u207b ions to form sodium chloride, which remains dissolved.<\/p>\n\n\n\n Total Ionic Equation:<\/strong><\/p>\n\n\n\n Fe\u00b3\u207a(aq) + 3Cl\u207b(aq) + 3Na\u207a(aq) + 3OH\u207b(aq) \u2192 Fe(OH)\u2083(s) + 3Na\u207a(aq) + 3Cl\u207b(aq)<\/p>\n\n\n\n Net Ionic Equation:<\/strong><\/p>\n\n\n\n Fe\u00b3\u207a(aq) + 3OH\u207b(aq) \u2192 Fe(OH)\u2083(s)<\/p>\n\n\n\n Spectator Ions:<\/strong><\/p>\n\n\n\n Na\u207a and Cl\u207b are unchanged on both sides of the equation and do not participate in the reaction.<\/p>\n\n\n\n Precipitate:<\/strong><\/p>\n\n\n\n Fe(OH)\u2083 \u2013 an insoluble brown solid.<\/p>\n\n\n\n Molecular Equation:<\/strong><\/p>\n\n\n\n 3MgSO\u2084(aq) + 2K\u2083PO\u2084(aq) \u2192 Mg\u2083(PO\u2084)\u2082(s) + 3K\u2082SO\u2084(aq)<\/p>\n\n\n\n Balanced Equation:<\/strong><\/p>\n\n\n\n Three magnesium sulfate units provide 3 Mg\u00b2\u207a ions, and two potassium phosphate units provide 2 PO\u2084\u00b3\u207b ions. These combine to form magnesium phosphate, Mg\u2083(PO\u2084)\u2082, an insoluble solid. Potassium sulfate remains in solution.<\/p>\n\n\n\n Total Ionic Equation:<\/strong><\/p>\n\n\n\n 3Mg\u00b2\u207a(aq) + 3SO\u2084\u00b2\u207b(aq) + 6K\u207a(aq) + 2PO\u2084\u00b3\u207b(aq) \u2192 Mg\u2083(PO\u2084)\u2082(s) + 6K\u207a(aq) + 3SO\u2084\u00b2\u207b(aq)<\/p>\n\n\n\n Net Ionic Equation:<\/strong><\/p>\n\n\n\n 3Mg\u00b2\u207a(aq) + 2PO\u2084\u00b3\u207b(aq) \u2192 Mg\u2083(PO\u2084)\u2082(s)<\/p>\n\n\n\n Spectator Ions:<\/strong><\/p>\n\n\n\n K\u207a and SO\u2084\u00b2\u207b are not involved in the actual precipitation.<\/p>\n\n\n\n Precipitate:<\/strong><\/p>\n\n\n\n Mg\u2083(PO\u2084)\u2082 \u2013 a white solid precipitate.<\/p>\n\n\n\n In both reactions, an insoluble hydroxide or phosphate compound<\/strong> forms as a precipitate. The net ionic equations<\/strong> clearly show the actual chemical change, while spectator ions<\/strong> remain unchanged. Recognizing these patterns is fundamental in predicting reaction outcomes in aqueous solutions.<\/p>\n\n\n\n Iron(III) chloride and sodium hydroxide: FeCl3 + NaOH \u00e2\u2020\u2019 Fe(OH)3 + NaCl Balanced Equation: FeCl3 + 3NaOH \u00e2\u2020\u2019 Fe(OH)3 + 3NaCl Total Ionic Equation: Fe3+ + 3Cl- + 3Na+ + 3OH- \u00e2\u2020\u2019 Fe(OH)3 + 3Na+ + 3Cl- Net Ionic Equation: Fe3+ + 3OH- \u00e2\u2020\u2019 Fe(OH)3 Spectator Ions: Na+ and Cl- Precipitate: Fe(OH)3 Magnesium sulfate and […]<\/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-233820","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/233820","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=233820"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/233820\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=233820"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=233820"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=233820"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\n\n\n\nReaction 1: Iron(III) chloride and sodium hydroxide<\/strong><\/h3>\n\n\n\n
\n\n\n\nReaction 2: Magnesium sulfate and potassium phosphate<\/strong><\/h3>\n\n\n\n
\n\n\n\nConclusion:<\/h3>\n\n\n\n
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