Question

HF form stronger H-bond than H2O. Still ∆Hvap of HF is lower than
that of H2O- explain by giving resason.

Answer 1

Because in hf intra molecular hydrogen bonding is present while in h2o inter molecular hydrogen bonding is present. H2O have greater boiling point than HF because H2O can form 4 hydrogen bond while HF have 2 hydrogen bond and to break all the hydrogen bonds more energy is needed by H2O than HF.