{"id":222954,"date":"2025-06-01T06:20:23","date_gmt":"2025-06-01T06:20:23","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=222954"},"modified":"2025-06-01T06:20:25","modified_gmt":"2025-06-01T06:20:25","slug":"what-is-the-mass-of-0-042-moles-c8h18-a-0-0178-b-0-370-c-0-500-d-4-80-e-921","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/06\/01\/what-is-the-mass-of-0-042-moles-c8h18-a-0-0178-b-0-370-c-0-500-d-4-80-e-921\/","title":{"rendered":"What is the mass of 0.042 moles C8H18? a. 0.0178 b. 0.370 c. 0.500 d. 4.80 e. 921"},"content":{"rendered":"\n


What is the mass of 0.042 moles C8H18? a. 0.0178 b. 0.370 c. 0.500 d. 4.80 e. 921<\/p>\n\n\n\n

The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n

To find the mass of 0.042 moles of C\u2088H\u2081\u2088 (octane)<\/strong>, we use the formula: Mass=Moles\u00d7Molar Mass\\text{Mass} = \\text{Moles} \\times \\text{Molar Mass}<\/p>\n\n\n\n

Step 1: Determine the molar mass of C\u2088H\u2081\u2088<\/h3>\n\n\n\n

Octane has 8 carbon atoms and 18 hydrogen atoms.<\/p>\n\n\n\n

    \n
  • Carbon (C): 12.01 g\/mol<\/li>\n\n\n\n
  • Hydrogen (H): 1.008 g\/mol<\/li>\n<\/ul>\n\n\n\n

    Molar Mass of C\u2088H\u2081\u2088=(8\u00d712.01)+(18\u00d71.008)=96.08+18.144=114.224\u2009g\/mol\\text{Molar Mass of C\u2088H\u2081\u2088} = (8 \\times 12.01) + (18 \\times 1.008) = 96.08 + 18.144 = 114.224 \\, \\text{g\/mol}<\/p>\n\n\n\n

    Step 2: Multiply by number of moles<\/h3>\n\n\n\n

    Mass=0.042\u2009mol\u00d7114.224\u2009g\/mol\u22484.80\u2009g\\text{Mass} = 0.042 \\, \\text{mol} \\times 114.224 \\, \\text{g\/mol} \\approx 4.80 \\, \\text{g}<\/p>\n\n\n\n

    Correct Answer: d. 4.80<\/strong><\/h3>\n\n\n\n
    \n\n\n\n

    Explanation<\/h3>\n\n\n\n

    To solve this problem, we apply a fundamental concept in chemistry: the relationship between moles and mass. Moles serve as a bridge between the number of particles in a substance and its measurable mass. The formula for converting moles to mass is: Mass (g)=Moles\u00d7Molar Mass (g\/mol)\\text{Mass (g)} = \\text{Moles} \\times \\text{Molar Mass (g\/mol)}<\/p>\n\n\n\n

    Here, we’re given 0.042 moles of C\u2088H\u2081\u2088<\/strong>, which is octane<\/strong>, a common hydrocarbon found in gasoline. Our task is to convert this quantity to grams. To do this, we must first calculate the molar mass<\/strong> of octane.<\/p>\n\n\n\n

    Octane consists of 8 carbon atoms and 18 hydrogen atoms. Using the periodic table, we find that the atomic mass of carbon is approximately 12.01 g\/mol and that of hydrogen is about 1.008 g\/mol. The molar mass of octane is then the sum of the masses of its constituent atoms: (8\u00d712.01)+(18\u00d71.008)=114.224\u2009g\/mol(8 \\times 12.01) + (18 \\times 1.008) = 114.224 \\, \\text{g\/mol}<\/p>\n\n\n\n

    With the molar mass known, we multiply by the number of moles: 0.042\u2009mol\u00d7114.224\u2009g\/mol=4.80\u2009g0.042 \\, \\text{mol} \\times 114.224 \\, \\text{g\/mol} = 4.80 \\, \\text{g}<\/p>\n\n\n\n

    Thus, 0.042 moles of octane has a mass of 4.80 grams<\/strong>, making option d<\/strong> the correct answer. This type of calculation is essential in stoichiometry, allowing chemists to relate quantities of substances in reactions.<\/p>\n\n\n\n

    \"\"<\/figure>\n","protected":false},"excerpt":{"rendered":"

    What is the mass of 0.042 moles C8H18? a. 0.0178 b. 0.370 c. 0.500 d. 4.80 e. 921 The Correct Answer and Explanation is: To find the mass of 0.042 moles of C\u2088H\u2081\u2088 (octane), we use the formula: Mass=Moles\u00d7Molar Mass\\text{Mass} = \\text{Moles} \\times \\text{Molar Mass} Step 1: Determine the molar mass of C\u2088H\u2081\u2088 Octane has 8 […]<\/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-222954","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/222954","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=222954"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/222954\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=222954"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=222954"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=222954"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}