The n-alkanes are straight chain molecules,but there are also branched alkanes(isomers). CH CH,一CH,-CH,-CH3 CH,一CH-CH butane (n-butane) isobutane CH, CH CH,一CH2CH2一CH2-CH3 CH;CH-CH,-CH, CH;C-CH, pentane (n-pentane) isopentane CH neopentane Any series that differs only by an increasing number of-CH2-groups is known as a Homologous series. The individual members are said to be homologs of each other. Ch03 Alkanes (landscape) Page 2Ch03 Alkanes (landscape) Page 2 The n-alkanes are straight chain molecules, but there are also branched alkanes (isomers). Any series that differs only by an increasing number of –CH2- groups is known as a Homologous series. The individual members are said to be homologs of each other