Hydrogen fluoride (HF) has a lower boiling point than water (H2O), even though fluoride (F) has a greater electronegativity than oxygen (O). Why do you think that is?

Question

Hydrogen fluoride (HF) has a lower boiling point than water (H₂O), even though fluoride (F) has a greater electronegativity than oxygen (O). Why do you think that is?

Answer 1

H₂O contains more hydrogen bonding than HF so even though the attraction between F and H may be stronger than that between O and H (in water), each H₂O molecule is hydrogen bonded to 4 other water molecules, but each HI molecule is hydrogen bonded to only 2 other HI molecules.