{"id":31,"date":"2024-10-24T12:07:13","date_gmt":"2024-10-24T16:07:13","guid":{"rendered":"https:\/\/sites.temple.edu\/chemdemo\/?p=31"},"modified":"2024-10-25T16:22:14","modified_gmt":"2024-10-25T20:22:14","slug":"precipitation-reaction","status":"publish","type":"post","link":"https:\/\/sites.temple.edu\/chemdemo\/2024\/10\/24\/precipitation-reaction\/","title":{"rendered":"Precipitation Reaction"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">Purpose<\/h2>\n\n\n\n<p>Show the nature of a precipitation reaction and explain the name.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Procedure<\/h2>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Solution Preparation<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Prepare roughly 1 M solutions of lead nitrate (Pb(NO\u2083)\u2082) and potassium iodide (KI).<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Reaction Setup<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Place some potassium iodide solution in a large (100 mL) graduated cylinder.<\/li>\n\n\n\n<li>Add a few drops of lead nitrate to the potassium iodide solution.<\/li>\n\n\n\n<li>Observe the formation of a yellow precipitate (lead iodide, PbI\u2082) that sinks to the bottom of the cylinder.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Demonstration<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Repeat the experiment using a petri dish on a document projector.<\/li>\n\n\n\n<li>Show that the yellow precipitate is a solid by scraping it with a spatula.<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n<h2 class=\"wp-block-heading\">Reactions Overview<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. Single Displacement\/Oxidation-Reduction<\/h3>\n\n\n\n<p>Zn<sub>0<\/sub>\u200b(s) + Pb(NO<sub>3\u200b<\/sub>)<sub>2<\/sub>\u200b (aq) \u2192 Zn(NO<sub>3<\/sub>\u200b)<sub>2<\/sub>\u200b (aq) + Pb<sub>0<\/sub>\u200b (s)<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">2. Double Replacement\/Precipitation<\/h3>\n\n\n\n<p>2 NaI (aq) + Pb(NO<sub>3<\/sub>\u200b)<sub>2<\/sub>\u200b (aq) \u2192 2 NaNO<sub>3<\/sub>\u200b (aq) + PbI<sub>2<\/sub>\u200b (s)<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">3. Gas Evolution<\/h3>\n\n\n\n<p>Na<sub>2\u200b<\/sub>CO<sub>3<\/sub>\u200b (aq) + 2 H<sub>3<\/sub>\u200bCCOOH (aq) \u2192H<sub>2<\/sub>\u200bO (l) + CO<sub>2\u200b<\/sub> (g) + 2 CH<sub>3<\/sub>\u200bCOO\u2212Na+ (aq)<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">4. Decomposition<\/h3>\n\n\n\n<p>MnO<sub>2<\/sub>\u200b (s) + 2 H<sub>2<\/sub>\u200bO<sub>2<\/sub>\u200b (aq) \u2192 2 H<sub>2<\/sub>\u200bO (aq) + O<sub>2<\/sub>\u200b(g) + MnO<sub>2<\/sub>\u200b(s)<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">5. Organic Decomposition<\/h3>\n\n\n\n<p>C<sub>6\u200b<\/sub>H<sub>12<\/sub>\u200bO<sub>6<\/sub>\u200b + H<sub>2<\/sub>\u200bSO<sub>4<\/sub>\u200b \u2192 6 H<sub>2<\/sub>\u200bO + 6 C (s)<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Purpose Show the nature of a precipitation reaction and explain the name. Procedure Reactions Overview 1. Single Displacement\/Oxidation-Reduction Zn0\u200b(s) + Pb(NO3\u200b)2\u200b (aq) \u2192 Zn(NO3\u200b)2\u200b (aq)&#8230;<\/p>\n<div class=\"more-link-wrapper\"><a class=\"more-link\" href=\"https:\/\/sites.temple.edu\/chemdemo\/2024\/10\/24\/precipitation-reaction\/\">Continue Reading<span class=\"screen-reader-text\">Precipitation Reaction<\/span><\/a><\/div>\n","protected":false},"author":36673,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[],"class_list":["post-31","post","type-post","status-publish","format-standard","hentry","category-demonstrations","entry"],"_links":{"self":[{"href":"https:\/\/sites.temple.edu\/chemdemo\/wp-json\/wp\/v2\/posts\/31","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sites.temple.edu\/chemdemo\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sites.temple.edu\/chemdemo\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sites.temple.edu\/chemdemo\/wp-json\/wp\/v2\/users\/36673"}],"replies":[{"embeddable":true,"href":"https:\/\/sites.temple.edu\/chemdemo\/wp-json\/wp\/v2\/comments?post=31"}],"version-history":[{"count":1,"href":"https:\/\/sites.temple.edu\/chemdemo\/wp-json\/wp\/v2\/posts\/31\/revisions"}],"predecessor-version":[{"id":32,"href":"https:\/\/sites.temple.edu\/chemdemo\/wp-json\/wp\/v2\/posts\/31\/revisions\/32"}],"wp:attachment":[{"href":"https:\/\/sites.temple.edu\/chemdemo\/wp-json\/wp\/v2\/media?parent=31"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sites.temple.edu\/chemdemo\/wp-json\/wp\/v2\/categories?post=31"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sites.temple.edu\/chemdemo\/wp-json\/wp\/v2\/tags?post=31"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}