Boiling Points of Alkanes -Branched alkanes have less surface area contact,so weaker intermolecular forces. 400 300 CH3-(CH2)-CH3 200 urod n-alkanes 100 Sur!oq CH3 0 CH-(CH2)CH3 -100 isoalkanes CH3 -200 0 5 10 15 20 number of carbon atoms Boiling Points of Alkanes ▪Branched alkanes have less surface area contact, so weaker intermolecular forces