Answer:
Kr- dispersion forces
CBr4- dispersion forces
CH3OH - dispersion forces, dipole interaction, hydrogen bonding
NaF- ionic
Kr-<CBr4<CH3OH<NaF
Explanation:
The magnitude of intermolecular forces influences the boiling points of substances. The stronger the intermolecular forces the higher the boiling point.
The strongest intermolecular forces here is the Ionic bond hence it accounts for the highest boiling point followed by CH3OH having hydrogen bonding.
Though Krypton and CBr4 both have dipole interaction, the higher relative molecular mass of CBr4 makes it to have a higher boiling point than Kr