Common names Isobutane.“ isomer of butane” Isopentane, isohexane, etc, methyl branch on next-to-ast carbon in chain Neopentane, most highly branched Five possible isomers of hexane, 18 isomers of octane and 75 for decane! => Chapter 3Chapter 3 3 Common Names • Isobutane, “isomer of butane” • Isopentane, isohexane, etc., methyl branch on next-to-last carbon in chain. • Neopentane, most highly branched • Five possible isomers of hexane, 18 isomers of octane and 75 for decane! =>