{"id":273,"date":"2017-10-04T15:10:59","date_gmt":"2017-10-04T15:10:59","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/suny-mcc-organicchemistry\/?post_type=chapter&p=273"},"modified":"2017-10-18T19:06:39","modified_gmt":"2017-10-18T19:06:39","slug":"hybridization-structure-of-ethane","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/suny-mcc-organicchemistry\/chapter\/hybridization-structure-of-ethane\/","title":{"raw":"Hybridization: Structure of Ethane","rendered":"Hybridization: Structure of Ethane"},"content":{"raw":"
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\u00a0Hybrid Orbitals and the Structure of Ethane<\/h2>\r\n<\/div>\r\n
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Objective<\/h3>\r\nAfter completing this section, you should be able to describe the structure of ethane in terms of the sp<\/em>3<\/sup> hybridization of the two carbon atoms present in the molecule.<\/div>\r\n<\/div>\r\n
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Bonding in Ethane<\/h3>\r\nIn the ethane molecule, the bonding picture according to valence orbital theory is very similar to that of methane.\u00a0 Both carbons are sp3<\/sup>-hybridized, meaning that both have four bonds arranged with tetrahedral geometry.\u00a0The carbon-carbon bond, with a bond length of 1.54 \u00c5, is formed by overlap of one\u00a0 sp3<\/sup> orbital from each of the carbons, while the six carbon-hydrogen bonds are formed from overlaps between the remaining sp3<\/sup> orbitals on the two carbons and the 1s<\/em> orbitals of hydrogen atoms.\u00a0All of these are sigma bonds.\r\n\r\n\"image180.png\"\r\n\r\nBecause they are formed from the end-on-end overlap of two orbitals, sigma <\/em>bonds are free to rotate<\/em><\/span>.\u00a0 This means, in the case of ethane molecule, that the two methyl (CH3<\/sub>) groups can be pictured as two wheels on a hub, each one able to rotate freely with respect to the other.\r\n\r\n\"image182.png\"\r\n\r\nIn chapter 3 we will learn more about the implications of rotational freedom in sigma bonds, when we discuss the \u2018conformation\u2019 of organic molecules.\r\n\r\nThe sp3<\/sup> bonding picture is also used to described the bonding in amines, including ammonia, the simplest amine.\u00a0 Just like the carbon atom in methane, the central nitrogen in ammonia is sp3<\/sup>-hybridized.\u00a0 With nitrogen, however, there are five rather than four valence electrons to account for, meaning that three of the four hybrid orbitals are half-filled and available for bonding, while the fourth is fully occupied by a (non-bonding) pair of electrons.\r\n\r\nC2<\/sub>H4<\/sub>, also known as ethylene or ethene, is a gaseous material created synthetically through steam cracking. In nature, it is released in trace amounts by plants to signal their fruits to ripen. Ethene\u00a0consists of two sp\u200b2<\/sup>-hybridized carbon atoms, which are sigma bonded to each other and to two hydrogen atoms each. The remaining unhybridized p orbitals on the carbon form a pi bond, which gives ethene its reactivity.\r\n\r\n<\/div>\r\n
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Example<\/h3>\r\n
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\r\n\r\nDraw pentane, CH3<\/sub>CH2<\/sub>CH2<\/sub>CH2<\/sub>CH3<\/sub>, predict the bond angles within this molecule.<\/span>\r\n\r\n<\/div>\r\n
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All the bond angles will be the same size.<\/span><\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n

\u00a0[\/hidden-answer]<\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n
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Contributors<\/h3>\r\n