Question

London dispersion forces are the only significant factor affecting boiling point for all the following except?

a. CHF3

b. CH4

c. SO3

d. Ar

e. Br2

Answer 1

N​​​​​​2 , SO​​​3 , CH​​​​​4 , Ar are non- polar ​​​​​​because the net dipole moment in each case is zero.

CHF​​​​​​3 has each C-F bond is polar in nature due to this, the molecule has some net dipole moment. It has dipole- diople attraction which affect the boiling point.

Answer is (a).