ORGANIC CHEMISTRY Chapter l 1. 12B The Structure of ethane o sp3-Hybridized carbon atoms g I carbon-carbon o-bond and 6 carbon-hydrogen o- ds onas o Because a o-bond has cylindrical symmetry along the bond axis, rotation of groups joined by a single bond does not usually require a large amount of energy(13 26 kJ/mol). Consequently, groups joined by single bonds rotate relatively freely with respect to one another H H He H H Department of Chemistry, Xiamen UniversityORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 1 1.12B The Structure of Ethane sp3-Hybridized carbon atoms 1 carbon-carbon σ-bond and 6 carbon-hydrogen σ- bonds. Because a σ-bond has cylindrical symmetry along the bond axis, rotation of groups joined by a single bond does not usually require a large amount of energy (13- 26 kJ/mol). Consequently, groups joined by single bonds rotate relatively freely with respect to one another. C H H H C H H H