Which among the following has highest boilling point and why?
(b) Explain why boilling point of n-alkanes increases regularly with the increase in the number of carbon atoms .

Explanation

(a) Xe has highest van der Waals force because of having more electrons and large surface area
(b) This can be explained on the basis of inter particle forces. The pricipal intermolecular force in alkane is London dispersion forces With the increaswe in number of carbon atoms the molecular mass nad molecular size increase This results in increases in magnitude of London dispersion forces. Consequently the boiling point also increases .