Question

why does n-butyl bromide have higher b. p. than t-butyl bromide ?

Answer 1

Because there is higher vanderval force in n-butyl bromide

Answer 2

Hey !!

n-Butyl bromide is a straight chain whereas t-Butyl Bromide is branched. The intermolecular forces in both are DIPOLE - DIPOLE (Van der Waals)

Van der Waal forces are stronger when chain is straight than branched.

∴ Boiling point n Butyl Bromide > t-Butyl Bromide.

n-Butyl bromide has greater surface area.

Good luck !!