Question

For a particular alkyl group R, what is the correct order of boiling points of the following compounds?

(a) RBr > RCl > RF

(b) RF > RCl > RBr

(c) RCl > RBr > RF

(d) RF > RBr > RCl

I got this question during an interview for a job.

I would like to ask this question from Haloarenes Physical Properties topic in section Haloalkanes and Haloarenes of Chemistry – Class 12

Answer 1

Correct option is (a) RBr > RCl > RF

To explain I would say: As the size of halogen atom increases, the magnitude of van der Waal forces increases, that is why RF has the lowest boiling point as it is the smallest halogen atom with weakest van der Waal attraction.