{"id":186053,"date":"2025-01-24T05:27:00","date_gmt":"2025-01-24T05:27:00","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=186053"},"modified":"2025-01-24T05:27:03","modified_gmt":"2025-01-24T05:27:03","slug":"arrange-the-following-substances-in-order-of-decreasing-boiling-point","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/01\/24\/arrange-the-following-substances-in-order-of-decreasing-boiling-point\/","title":{"rendered":"Arrange the following substances in order of decreasing boiling point"},"content":{"rendered":"\n<p>Arrange the following substances in order of decreasing boiling point.<\/p>\n\n\n\n<p>(a) CH3CH2CH2CH3, H2NCH2CH2NH2,<\/p>\n\n\n\n<p>CH3CH2CH2NH2<\/p>\n\n\n\n<p>(b) ICl, Br2, N2<\/p>\n\n\n\n<p>(c) LiCl, CO2, CS2<\/p>\n\n\n\n<p><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-6-color\"><strong>The Correct Answer and Explanation is :<\/strong><\/mark><\/p>\n\n\n\n<p>Let&#8217;s break this down and analyze each set of compounds to arrange them in decreasing boiling point order.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">(a) CH3CH2CH2CH3, H2NCH2CH2NH2, CH3CH2CH2NH2<\/h3>\n\n\n\n<p>We are comparing three organic compounds with different types of intermolecular forces. Boiling points are significantly affected by the type of intermolecular forces present in a substance. Stronger intermolecular forces lead to higher boiling points.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>CH3CH2CH2CH3 (Butane)<\/strong>: This is a nonpolar molecule, and the primary intermolecular force is <strong>London dispersion forces<\/strong> (induced dipole-induced dipole interactions). It is the weakest of the intermolecular forces.<\/li>\n\n\n\n<li><strong>CH3CH2CH2NH2 (Propylamine)<\/strong>: This is a polar molecule due to the presence of an amine group (-NH2). The molecule can form <strong>hydrogen bonds<\/strong> (a relatively strong intermolecular force). This leads to a higher boiling point than that of butane.<\/li>\n\n\n\n<li><strong>H2NCH2CH2NH2 (Ethylamine)<\/strong>: This is a polar molecule as well, and like propylamine, it has <strong>hydrogen bonding<\/strong>. However, the presence of two -NH2 groups allows for stronger hydrogen bonding and increased surface area compared to propylamine, which generally results in a higher boiling point than that of propylamine.<\/li>\n<\/ul>\n\n\n\n<p><strong>Order of boiling points (decreasing):<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>H2NCH2CH2NH2<\/strong> (strong hydrogen bonding)<\/li>\n\n\n\n<li><strong>CH3CH2CH2NH2<\/strong> (hydrogen bonding)<\/li>\n\n\n\n<li><strong>CH3CH2CH2CH3<\/strong> (only London dispersion forces)<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\">(b) ICl, Br2, N2<\/h3>\n\n\n\n<p>Here, we have two halogen compounds and a nonpolar molecule.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>ICl<\/strong>: This is a polar molecule due to the difference in electronegativity between iodine and chlorine. The major intermolecular force in ICl is <strong>dipole-dipole interactions<\/strong>, but it also has <strong>London dispersion forces<\/strong>.<\/li>\n\n\n\n<li><strong>Br2<\/strong>: This is a nonpolar molecule, but it is relatively large and thus has <strong>strong London dispersion forces<\/strong>. As a result, its boiling point is higher than that of N2, but it is lower than that of ICl.<\/li>\n\n\n\n<li><strong>N2<\/strong>: Nitrogen is a nonpolar molecule, and the only intermolecular force present is <strong>London dispersion forces<\/strong>, which are relatively weak for such small molecules.<\/li>\n<\/ul>\n\n\n\n<p><strong>Order of boiling points (decreasing):<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>ICl<\/strong> (polar, dipole-dipole interactions + dispersion forces)<\/li>\n\n\n\n<li><strong>Br2<\/strong> (nonpolar, large molecule, strong dispersion forces)<\/li>\n\n\n\n<li><strong>N2<\/strong> (nonpolar, small molecule, weak dispersion forces)<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\">(c) LiCl, CO2, CS2<\/h3>\n\n\n\n<p>These are a mix of ionic and molecular compounds, and the boiling points are influenced by the types of forces involved.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>LiCl<\/strong>: This is an ionic compound, and ionic bonds are very strong. The strong electrostatic forces between the Li+ and Cl- ions lead to a high boiling point.<\/li>\n\n\n\n<li><strong>CS2<\/strong>: This is a nonpolar molecule, but it is relatively large. The main intermolecular forces are <strong>London dispersion forces<\/strong>, which are stronger than in smaller molecules but still weaker than ionic bonds.<\/li>\n\n\n\n<li><strong>CO2<\/strong>: This is a nonpolar molecule with <strong>London dispersion forces<\/strong>. However, it is smaller than CS2, so its boiling point will be lower than that of CS2.<\/li>\n<\/ul>\n\n\n\n<p><strong>Order of boiling points (decreasing):<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>LiCl<\/strong> (ionic bonds, strongest intermolecular forces)<\/li>\n\n\n\n<li><strong>CS2<\/strong> (nonpolar, large molecule with relatively strong dispersion forces)<\/li>\n\n\n\n<li><strong>CO2<\/strong> (nonpolar, small molecule with weak dispersion forces)<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\">Final Answer:<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>(a)<\/strong> H2NCH2CH2NH2 > CH3CH2CH2NH2 > CH3CH2CH2CH3<\/li>\n\n\n\n<li><strong>(b)<\/strong> ICl > Br2 > N2<\/li>\n\n\n\n<li><strong>(c)<\/strong> LiCl > CS2 > CO2<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Explanation:<\/h3>\n\n\n\n<p>The boiling point is influenced by the strength of the intermolecular forces. Ionic compounds, like <strong>LiCl<\/strong>, have very strong forces (ionic bonds), leading to higher boiling points. Molecules with hydrogen bonding, like <strong>H2NCH2CH2NH2<\/strong>, also tend to have higher boiling points. Nonpolar molecules like <strong>Br2<\/strong>, <strong>CS2<\/strong>, and <strong>CO2<\/strong> experience London dispersion forces, which are weaker than other intermolecular forces, resulting in lower boiling points.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Arrange the following substances in order of decreasing boiling point. (a) CH3CH2CH2CH3, H2NCH2CH2NH2, CH3CH2CH2NH2 (b) ICl, Br2, N2 (c) LiCl, CO2, CS2 The Correct Answer and Explanation is : Let&#8217;s break this down and analyze each set of compounds to arrange them in decreasing boiling point order. (a) CH3CH2CH2CH3, H2NCH2CH2NH2, CH3CH2CH2NH2 We are comparing three [&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-186053","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/186053","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=186053"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/186053\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=186053"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=186053"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=186053"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}