In chemistry, a homologous series is a series of organic compounds with a similar general formula, possessing similar chemical properties due to the presence of the same functional group, and shows a gradation in physical properties as a result of increase in molecular size and mass. For example, ethane has a higher boiling point than methane since it has more Van der Waals forces (intermolecular forces) with neighbouring molecules. This is due to the increase in the number of atoms making up the molecule. Each organic compound in a homologous series vary by an extra CH2 (or 14 atomic mass units) from the previous compound.
