The boiling point of 1−propanol, CH3CH2CH2OH, is 39.8 ° C and the boiling point of ethylene glycol, HOCH2CH2OH, is 245 ° C. Explain this large difference in boiling point in terms of structure and intermolecular forces in these substances. Answers: Ethylene glycol can form more hydrogen bonds. Propanol can form more hydrogen bonds. Ethylene glycol has a higher molar mass and therefore larger London dispersion forces. Propanol has a higher molar mass and therefore larger London dispersion forces.