{"id":249714,"date":"2025-07-09T19:18:58","date_gmt":"2025-07-09T19:18:58","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=249714"},"modified":"2025-07-09T19:19:02","modified_gmt":"2025-07-09T19:19:02","slug":"calculate-the-molar-mass-of-octane","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/07\/09\/calculate-the-molar-mass-of-octane\/","title":{"rendered":"\u00a0Calculate the molar mass of octane.\u00a0"},"content":{"rendered":"\n<pre id=\"preorder-ask-header-text\" class=\"wp-block-preformatted\">&nbsp;Calculate the molar mass of octane.&nbsp;<\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/07\/image-350.png\" alt=\"\" class=\"wp-image-249715\"\/><\/figure>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-0-color\">The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n<p><strong>114.2&nbsp;g\/mol<\/strong><\/p>\n\n\n\n<p>To calculate the molar mass of octane, we first need to determine its molecular formula from the given condensed structural formula, CH\u2083(CH\u2082)\u2086CH\u2083, and then sum the atomic masses of all the atoms in the molecule.<\/p>\n\n\n\n<p>First, let&#8217;s find the total number of carbon (C) and hydrogen (H) atoms. The formula shows one initial methyl group (CH\u2083), six repeating methylene groups (CH\u2082), and one final methyl group (CH\u2083).<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Carbon (C) atoms:<\/strong>\u00a0There is 1 carbon in the first CH\u2083, 6 carbons in the (CH\u2082)\u2086 part, and 1 carbon in the last CH\u2083. The total number of carbon atoms is 1 + 6 + 1 = 8.<\/li>\n\n\n\n<li><strong>Hydrogen (H) atoms:<\/strong>\u00a0There are 3 hydrogens in the first CH\u2083, 12 hydrogens in the (CH\u2082)\u2086 part (6 groups \u00d7 2 hydrogens each), and 3 hydrogens in the last CH\u2083. The total number of hydrogen atoms is 3 + 12 + 3 = 18.<br>So, the molecular formula for octane is C\u2088H\u2081\u2088.<\/li>\n<\/ul>\n\n\n\n<p>Next, we use the standard atomic masses for carbon and hydrogen, which can be found on the periodic table.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The atomic mass of Carbon (C) is approximately 12.011\u00a0g\/mol\u00a0.<\/li>\n\n\n\n<li>The atomic mass of Hydrogen (H) is approximately 1.008\u00a0g\/mol\u00a0.<\/li>\n<\/ul>\n\n\n\n<p>Now, we calculate the molar mass by multiplying the count of each atom by its respective atomic mass and adding the results together.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Mass from Carbon = 8 atoms \u00d7 12.011\u00a0g\/mol\u00a0= 96.088\u00a0g\/mol<\/li>\n\n\n\n<li>Mass from Hydrogen = 18 atoms \u00d7 1.008\u00a0g\/mol\u00a0= 18.144\u00a0g\/mol<\/li>\n<\/ul>\n\n\n\n<p>The total molar mass of octane is the sum of these values:<br>Molar Mass = 96.088&nbsp;g\/mol&nbsp;+ 18.144&nbsp;g\/mol&nbsp;= 114.232&nbsp;g\/mol&nbsp;.<\/p>\n\n\n\n<p>Finally, the question requires the answer to be rounded to one decimal place. The calculated value is 114.232. Since the second decimal digit (3) is less than 5, we round down, keeping the first decimal digit as it is.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/07\/learnexams-banner6-37.jpeg\" alt=\"\" class=\"wp-image-249716\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>&nbsp;Calculate the molar mass of octane.&nbsp; The Correct Answer and Explanation is: 114.2&nbsp;g\/mol To calculate the molar mass of octane, we first need to determine its molecular formula from the given condensed structural formula, CH\u2083(CH\u2082)\u2086CH\u2083, and then sum the atomic masses of all the atoms in the molecule. First, let&#8217;s find the total number of [&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-249714","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/249714","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=249714"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/249714\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=249714"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=249714"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=249714"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}