{"id":214494,"date":"2025-05-14T13:06:21","date_gmt":"2025-05-14T13:06:21","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=214494"},"modified":"2025-05-14T13:06:23","modified_gmt":"2025-05-14T13:06:23","slug":"a-pentane-c5h12-molecule-is-nonpolar-while-water-h2o-is-polar","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/05\/14\/a-pentane-c5h12-molecule-is-nonpolar-while-water-h2o-is-polar\/","title":{"rendered":"A pentane (C5H12) molecule is nonpolar while water (H2O) is polar"},"content":{"rendered":"\n

A pentane (C5H12) molecule is nonpolar while water (H2O) is polar. According to this information: a. Pentane has a higher melting point and boiling point than water b. Water has a higher melting point than pentane, but pentane has a higher boiling point than water c. Water has a higher melting point and boiling point than pentane d. Pentane has a higher melting point than water, but water has a higher boiling point than pentane<\/p>\n\n\n\n

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

Correct Answer: c. Water has a higher melting point and boiling point than pentane<\/strong><\/p>\n\n\n\n

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

To understand why water has a higher melting point<\/strong> and boiling point<\/strong> than pentane<\/strong>, we must consider the nature of intermolecular forces<\/strong>.<\/p>\n\n\n\n

\n\n\n\n

1. Molecular Polarity and Intermolecular Forces:<\/strong><\/h3>\n\n\n\n
    \n
  • Water (H\u2082O)<\/strong> is a polar<\/strong> molecule. The oxygen atom has a partial negative charge, while the hydrogen atoms have partial positive charges, leading to a dipole. More importantly, water molecules can form hydrogen bonds<\/strong>, which are a strong type of dipole-dipole interaction.<\/li>\n\n\n\n
  • Pentane (C\u2085H\u2081\u2082)<\/strong> is a nonpolar<\/strong> hydrocarbon. Its molecules only exhibit London dispersion forces<\/strong>, which are the weakest type of intermolecular forces. These are temporary, induced dipoles that arise due to momentary shifts in electron clouds.<\/li>\n<\/ul>\n\n\n\n
    \n\n\n\n

    2. Boiling and Melting Points:<\/strong><\/h3>\n\n\n\n
      \n
    • Boiling Point<\/strong>: The stronger the intermolecular forces, the more energy is required to separate the molecules from each other and convert the substance into a gas.<\/li>\n\n\n\n
    • Water, due to hydrogen bonding, has a high boiling point of 100\u00b0C<\/strong>.<\/li>\n\n\n\n
    • Pentane has a boiling point of about 36\u00b0C<\/strong>, much lower because it only has weak London dispersion forces.<\/li>\n\n\n\n
    • Melting Point<\/strong>: Similarly, stronger intermolecular forces result in a higher melting point.<\/li>\n\n\n\n
    • Water has a melting point of 0\u00b0C<\/strong>, while pentane melts at about \u2212130\u00b0C<\/strong>, again showing water\u2019s stronger bonding.<\/li>\n<\/ul>\n\n\n\n
      \n\n\n\n

      3. Conclusion:<\/strong><\/h3>\n\n\n\n

      Water has both a higher melting point and boiling point<\/strong> than pentane because its molecules are held together by hydrogen bonds<\/strong>, which are significantly stronger than the London dispersion forces that hold pentane molecules together. These stronger forces require more energy to overcome, resulting in higher phase change temperatures for water.<\/p>\n\n\n\n

      Thus, the correct answer is c. Water has a higher melting point and boiling point than pentane<\/strong>.<\/p>\n","protected":false},"excerpt":{"rendered":"

      A pentane (C5H12) molecule is nonpolar while water (H2O) is polar. According to this information: a. Pentane has a higher melting point and boiling point than water b. Water has a higher melting point than pentane, but pentane has a higher boiling point than water c. Water has a higher melting point and boiling point […]<\/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-214494","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/214494","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=214494"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/214494\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=214494"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=214494"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=214494"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}