{"id":3060,"date":"2016-08-25T21:37:15","date_gmt":"2016-08-25T21:37:15","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/?post_type=chapter&#038;p=3060"},"modified":"2016-08-26T02:24:53","modified_gmt":"2016-08-26T02:24:53","slug":"multiple-covalent-bonds","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/chapter\/multiple-covalent-bonds\/","title":{"raw":"Multiple Covalent Bonds","rendered":"Multiple Covalent Bonds"},"content":{"raw":"<div>\r\n<div class=\"textbox learning-objectives\">\r\n<h3>Learning Objectives<\/h3>\r\n<ul>\r\n \t<li>Define double bond.<\/li>\r\n \t<li>Define triple bond.<\/li>\r\n \t<li>Draw Lewis electron dot structures for compounds containing double or triple bonds.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\n<div class=\"textbox examples\">\r\n<h3>What do you do with your leftovers?<\/h3>\r\n<img class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19211438\/20140811155251520534.jpg\" alt=\"Electron symbols in a box\" width=\"150\" \/>\r\n\r\nWhen working with covalent structures, it sometimes looks like you have leftover electrons. You apply the rules you learned so far and there are still some electrons hanging out there unattached. You can\u2019t just leave them there. So where do you put them?\r\n\r\n<\/div>\r\n<h2><strong> Multiple Covalent Bonds <\/strong><\/h2>\r\nSome molecules are not able to satisfy the octet rule by making only single covalent bonds between the atoms. Consider the compound ethene, which has a molecular formula of C <sub> 2 <\/sub> H <sub> 4 <\/sub> . The carbon atoms are bonded together, with each carbon also being bonded to two hydrogen atoms.\r\n\r\n<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19211439\/ae2abd6510a185a4cc342103a9240cf0.png\" alt=\"&amp; text{two C atoms} = 2 times 4 = 8 text{valence electrons} \\&amp; text{four H atoms} = 4 times 1 = 4 text{valence electrons} \\&amp; text{total of 12 valence electrons in the molecule}\" width=\"343\" height=\"67\" \/>\r\n\r\nIf the Lewis electron dot structure was drawn with a single bond between the carbon atoms and with the octet rule followed, it would look like this:\r\n<div>\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"192\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19211440\/20140811155251604236.png\" alt=\"Incorrect Lewis dot structure of ethene\" width=\"192\" height=\"149\" longdesc=\"Incorrect%20dot%20structure%20of%20ethene.\" \/> Figure 1. Incorrect dot structure of ethene.[\/caption]\r\n\r\n&nbsp;\r\n\r\n<\/div>\r\nThis Lewis structure is incorrect because it contains a total of 14 electrons. However, the Lewis structure can be changed by eliminating the lone pairs on the carbon atoms and having the share two pairs instead of only one pair.\r\n<div>\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"192\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19211441\/20140811155251743910.png\" alt=\"Correct Lewis dot structure of ethene\" width=\"192\" height=\"93\" longdesc=\"Correct%20dot%20structure%20for%20ethene.\" \/> Figure 2. Correct dot structure for ethene.[\/caption]\r\n\r\n&nbsp;\r\n\r\n<\/div>\r\nA <strong> double covalent bond <\/strong> is a covalent bond formed by atoms that share two pairs of electrons. The double covalent bond that occurs between the two carbon atoms in ethane can also be represented by a structural formula and with a molecular model as shown below.\r\n<div>\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"500\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19211442\/20140811155251899369.png\" alt=\"Structural and molecular model of ethene\" width=\"500\" height=\"229\" longdesc=\"%28A%29%20The%20structural%20model%20for%20C%3Csub%3E2%3C\/sub%3EH%3Csub%3E4%3C\/sub%3E%20consists%20of%20a%20double%20covalent%20bond%20between%20the%20two%20carbon%20atoms%20and%20single%20bonds%20to%20the%20hydrogen%20atoms.%20%28B%29%20Molecular%20model%20of%20C%3Csub%3E2%3C\/sub%3EH%3Csub%3E4%3C\/sub%3E.\" \/> Figure 3. (A) The structural model for C<sub>2<\/sub>H<sub>4<\/sub> consists of a double covalent bond between the two carbon atoms and single bonds to the hydrogen atoms. (B) Molecular model of C<sub>2<\/sub> H<sub>4<\/sub>.[\/caption]\r\n\r\n<\/div>\r\nA <strong> triple covalent bond <\/strong> is a covalent bond formed by atoms that share three pairs of electrons. The element nitrogen is a gas that composes the majority of Earth\u2019s atmosphere. A nitrogen atom has five valence electrons, which can be shown as one pair and three single electrons. When combining with another nitrogen atom to form a diatomic molecule, the three single electrons on each atom combine to form three shared pairs of electrons.\r\n<div>\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"500\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19211443\/20140811155252025129.png\" alt=\"A triple bond in nitrogen gas\" width=\"500\" height=\"185\" longdesc=\"Triple%20bond%20in%20N%3Csub%3E2%3C\/sub%3E.\" \/> Figure 4. Triple bond in N<sub>2<\/sub>.[\/caption]\r\n\r\n&nbsp;\r\n\r\n<\/div>\r\nEach nitrogen atom follows the octet rule with one lone pair of electrons and six electrons that are shared between the atoms.\r\n<div class=\"textbox key-takeaways\">\r\n<h3>Summary<\/h3>\r\n<ul>\r\n \t<li>Lewis structures can be drawn for molecules that share multiple pairs of electrons.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div class=\"textbox exercises\">\r\n<h3>Practice<\/h3>\r\nRead the material at the link below and take the quiz (Test Bite).\r\n\r\n<a href=\"http:\/\/www.bbc.co.uk\/schools\/gcsebitesize\/science\/add_aqa_pre_2011\/atomic\/covalentrev1.shtml\"> http:\/\/www.bbc.co.uk\/schools\/gcsebitesize\/science\/add_aqa_pre_2011\/atomic\/covalentrev1.shtml<\/a>\r\n\r\n<\/div>\r\n<div class=\"textbox exercises\">\r\n<h3>Exercises<\/h3>\r\n<ol>\r\n \t<li>Why is the first ethene Lewis structure incorrect?<\/li>\r\n \t<li>What do the single electrons in nitrogen do to for a triple bond?<\/li>\r\n \t<li>Draw the Lewis structure for ethyne C <sub> 2 <\/sub> H <sub> 2 <\/sub> .<\/li>\r\n<\/ol>\r\n<\/div>\r\n<h2>\u00a0Glossary<\/h2>\r\n<div>\r\n<ul>\r\n \t<li><strong> double covalent bond: <\/strong> A covalent bond formed by atoms that share two pairs of electrons.<\/li>\r\n \t<li><strong> triple covalent bond: <\/strong> A covalent bond formed by atoms that share three pairs of electrons.<\/li>\r\n<\/ul>\r\n[reveal-answer q=\"836080\"]Show References[\/reveal-answer] [hidden-answer a=\"836080\"]\r\n<h2>References<\/h2>\r\n<ol>\r\n \t<li>CK-12 Foundation - Joy Sheng.<\/li>\r\n \t<li>CK-12 Foundation - Joy Sheng.<\/li>\r\n \t<li>CK-12 Foundation - Joy Sheng.<\/li>\r\n \t<li>Ben Mills (Wikimedia: Benjah-bmm27). (A) <a href=\"http:\/\/commons.wikimedia.org\/wiki\/File:Ethylene-CRC-MW-dimensions-2D-Vector.svg\" target=\"_blank\">http:\/\/commons.wikimedia.org\/wiki\/File:Ethylene-CRC-MW-dimensions-2D-Vector.svg<\/a>; (B) <a href=\"http:\/\/commons.wikimedia.org\/wiki\/File:Ethylene-CRC-MW-3D-balls.png\" target=\"_blank\">http:\/\/commons.wikimedia.org\/wiki\/File:Ethylene-CRC-MW-3D-balls.png<\/a> .<\/li>\r\n \t<li>CK-12 Foundation - Joy Sheng, using 3D molecular structure by Ben Mills (Wikimedia: Benjah-bmm27). Molecular structure: <a href=\"http:\/\/commons.wikimedia.org\/wiki\/File:Nitrogen-3D-vdW.png\" target=\"_blank\">http:\/\/commons.wikimedia.org\/wiki\/File:Nitrogen-3D-vdW.png<\/a>.<\/li>\r\n<\/ol>\r\n[\/hidden-answer]\r\n\r\n<\/div>","rendered":"<div>\n<div class=\"textbox learning-objectives\">\n<h3>Learning Objectives<\/h3>\n<ul>\n<li>Define double bond.<\/li>\n<li>Define triple bond.<\/li>\n<li>Draw Lewis electron dot structures for compounds containing double or triple bonds.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<div class=\"textbox examples\">\n<h3>What do you do with your leftovers?<\/h3>\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19211438\/20140811155251520534.jpg\" alt=\"Electron symbols in a box\" width=\"150\" \/><\/p>\n<p>When working with covalent structures, it sometimes looks like you have leftover electrons. You apply the rules you learned so far and there are still some electrons hanging out there unattached. You can\u2019t just leave them there. So where do you put them?<\/p>\n<\/div>\n<h2><strong> Multiple Covalent Bonds <\/strong><\/h2>\n<p>Some molecules are not able to satisfy the octet rule by making only single covalent bonds between the atoms. Consider the compound ethene, which has a molecular formula of C <sub> 2 <\/sub> H <sub> 4 <\/sub> . The carbon atoms are bonded together, with each carbon also being bonded to two hydrogen atoms.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19211439\/ae2abd6510a185a4cc342103a9240cf0.png\" alt=\"&amp; text{two C atoms} = 2 times 4 = 8 text{valence electrons} \\&amp; text{four H atoms} = 4 times 1 = 4 text{valence electrons} \\&amp; text{total of 12 valence electrons in the molecule}\" width=\"343\" height=\"67\" \/><\/p>\n<p>If the Lewis electron dot structure was drawn with a single bond between the carbon atoms and with the octet rule followed, it would look like this:<\/p>\n<div>\n<div style=\"width: 202px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19211440\/20140811155251604236.png\" alt=\"Incorrect Lewis dot structure of ethene\" width=\"192\" height=\"149\" longdesc=\"Incorrect%20dot%20structure%20of%20ethene.\" \/><\/p>\n<p class=\"wp-caption-text\">Figure 1. Incorrect dot structure of ethene.<\/p>\n<\/div>\n<p>&nbsp;<\/p>\n<\/div>\n<p>This Lewis structure is incorrect because it contains a total of 14 electrons. However, the Lewis structure can be changed by eliminating the lone pairs on the carbon atoms and having the share two pairs instead of only one pair.<\/p>\n<div>\n<div style=\"width: 202px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19211441\/20140811155251743910.png\" alt=\"Correct Lewis dot structure of ethene\" width=\"192\" height=\"93\" longdesc=\"Correct%20dot%20structure%20for%20ethene.\" \/><\/p>\n<p class=\"wp-caption-text\">Figure 2. Correct dot structure for ethene.<\/p>\n<\/div>\n<p>&nbsp;<\/p>\n<\/div>\n<p>A <strong> double covalent bond <\/strong> is a covalent bond formed by atoms that share two pairs of electrons. The double covalent bond that occurs between the two carbon atoms in ethane can also be represented by a structural formula and with a molecular model as shown below.<\/p>\n<div>\n<div style=\"width: 510px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19211442\/20140811155251899369.png\" alt=\"Structural and molecular model of ethene\" width=\"500\" height=\"229\" longdesc=\"%28A%29%20The%20structural%20model%20for%20C%3Csub%3E2%3C\/sub%3EH%3Csub%3E4%3C\/sub%3E%20consists%20of%20a%20double%20covalent%20bond%20between%20the%20two%20carbon%20atoms%20and%20single%20bonds%20to%20the%20hydrogen%20atoms.%20%28B%29%20Molecular%20model%20of%20C%3Csub%3E2%3C\/sub%3EH%3Csub%3E4%3C\/sub%3E.\" \/><\/p>\n<p class=\"wp-caption-text\">Figure 3. (A) The structural model for C<sub>2<\/sub>H<sub>4<\/sub> consists of a double covalent bond between the two carbon atoms and single bonds to the hydrogen atoms. (B) Molecular model of C<sub>2<\/sub> H<sub>4<\/sub>.<\/p>\n<\/div>\n<\/div>\n<p>A <strong> triple covalent bond <\/strong> is a covalent bond formed by atoms that share three pairs of electrons. The element nitrogen is a gas that composes the majority of Earth\u2019s atmosphere. A nitrogen atom has five valence electrons, which can be shown as one pair and three single electrons. When combining with another nitrogen atom to form a diatomic molecule, the three single electrons on each atom combine to form three shared pairs of electrons.<\/p>\n<div>\n<div style=\"width: 510px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19211443\/20140811155252025129.png\" alt=\"A triple bond in nitrogen gas\" width=\"500\" height=\"185\" longdesc=\"Triple%20bond%20in%20N%3Csub%3E2%3C\/sub%3E.\" \/><\/p>\n<p class=\"wp-caption-text\">Figure 4. Triple bond in N<sub>2<\/sub>.<\/p>\n<\/div>\n<p>&nbsp;<\/p>\n<\/div>\n<p>Each nitrogen atom follows the octet rule with one lone pair of electrons and six electrons that are shared between the atoms.<\/p>\n<div class=\"textbox key-takeaways\">\n<h3>Summary<\/h3>\n<ul>\n<li>Lewis structures can be drawn for molecules that share multiple pairs of electrons.<\/li>\n<\/ul>\n<\/div>\n<div class=\"textbox exercises\">\n<h3>Practice<\/h3>\n<p>Read the material at the link below and take the quiz (Test Bite).<\/p>\n<p><a href=\"http:\/\/www.bbc.co.uk\/schools\/gcsebitesize\/science\/add_aqa_pre_2011\/atomic\/covalentrev1.shtml\"> http:\/\/www.bbc.co.uk\/schools\/gcsebitesize\/science\/add_aqa_pre_2011\/atomic\/covalentrev1.shtml<\/a><\/p>\n<\/div>\n<div class=\"textbox exercises\">\n<h3>Exercises<\/h3>\n<ol>\n<li>Why is the first ethene Lewis structure incorrect?<\/li>\n<li>What do the single electrons in nitrogen do to for a triple bond?<\/li>\n<li>Draw the Lewis structure for ethyne C <sub> 2 <\/sub> H <sub> 2 <\/sub> .<\/li>\n<\/ol>\n<\/div>\n<h2>\u00a0Glossary<\/h2>\n<div>\n<ul>\n<li><strong> double covalent bond: <\/strong> A covalent bond formed by atoms that share two pairs of electrons.<\/li>\n<li><strong> triple covalent bond: <\/strong> A covalent bond formed by atoms that share three pairs of electrons.<\/li>\n<\/ul>\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"q836080\">Show References<\/span> <\/p>\n<div id=\"q836080\" class=\"hidden-answer\" style=\"display: none\">\n<h2>References<\/h2>\n<ol>\n<li>CK-12 Foundation &#8211; Joy Sheng.<\/li>\n<li>CK-12 Foundation &#8211; Joy Sheng.<\/li>\n<li>CK-12 Foundation &#8211; Joy Sheng.<\/li>\n<li>Ben Mills (Wikimedia: Benjah-bmm27). (A) <a href=\"http:\/\/commons.wikimedia.org\/wiki\/File:Ethylene-CRC-MW-dimensions-2D-Vector.svg\" target=\"_blank\">http:\/\/commons.wikimedia.org\/wiki\/File:Ethylene-CRC-MW-dimensions-2D-Vector.svg<\/a>; (B) <a href=\"http:\/\/commons.wikimedia.org\/wiki\/File:Ethylene-CRC-MW-3D-balls.png\" target=\"_blank\">http:\/\/commons.wikimedia.org\/wiki\/File:Ethylene-CRC-MW-3D-balls.png<\/a> .<\/li>\n<li>CK-12 Foundation &#8211; Joy Sheng, using 3D molecular structure by Ben Mills (Wikimedia: Benjah-bmm27). Molecular structure: <a href=\"http:\/\/commons.wikimedia.org\/wiki\/File:Nitrogen-3D-vdW.png\" target=\"_blank\">http:\/\/commons.wikimedia.org\/wiki\/File:Nitrogen-3D-vdW.png<\/a>.<\/li>\n<\/ol>\n<\/div>\n<\/div>\n<\/div>\n\n\t\t\t <section class=\"citations-section\" role=\"contentinfo\">\n\t\t\t <h3>Candela Citations<\/h3>\n\t\t\t\t\t <div>\n\t\t\t\t\t\t <div id=\"citation-list-3060\">\n\t\t\t\t\t\t\t <div class=\"licensing\"><div class=\"license-attribution-dropdown-subheading\">CC licensed content, Shared previously<\/div><ul class=\"citation-list\"><li>Chemistry Concepts Intermediate. <strong>Authored by<\/strong>: Calbreath, Baxter, et al.. <strong>Provided by<\/strong>: CK12.org. <strong>Located at<\/strong>: <a target=\"_blank\" href=\"http:\/\/www.ck12.org\/book\/CK-12-Chemistry-Concepts-Intermediate\/\">http:\/\/www.ck12.org\/book\/CK-12-Chemistry-Concepts-Intermediate\/<\/a>. <strong>License<\/strong>: <em><a target=\"_blank\" rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC: Attribution-NonCommercial<\/a><\/em><\/li><\/ul><\/div>\n\t\t\t\t\t\t <\/div>\n\t\t\t\t\t <\/div>\n\t\t\t <\/section>","protected":false},"author":17,"menu_order":5,"template":"","meta":{"_candela_citation":"[{\"type\":\"cc\",\"description\":\"Chemistry Concepts Intermediate\",\"author\":\"Calbreath, Baxter, et al.\",\"organization\":\"CK12.org\",\"url\":\"http:\/\/www.ck12.org\/book\/CK-12-Chemistry-Concepts-Intermediate\/\",\"project\":\"\",\"license\":\"cc-by-nc\",\"license_terms\":\"\"}]","CANDELA_OUTCOMES_GUID":"","pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-3060","chapter","type-chapter","status-publish","hentry"],"part":2330,"_links":{"self":[{"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/pressbooks\/v2\/chapters\/3060","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/wp\/v2\/users\/17"}],"version-history":[{"count":6,"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/pressbooks\/v2\/chapters\/3060\/revisions"}],"predecessor-version":[{"id":3310,"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/pressbooks\/v2\/chapters\/3060\/revisions\/3310"}],"part":[{"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/pressbooks\/v2\/parts\/2330"}],"metadata":[{"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/pressbooks\/v2\/chapters\/3060\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/wp\/v2\/media?parent=3060"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/pressbooks\/v2\/chapter-type?post=3060"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/wp\/v2\/contributor?post=3060"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/wp\/v2\/license?post=3060"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}