Hydrogen Bonding

Not all dipole – dipole interactions are responsible for hydrogen bonding, so assertion A is false. F is most E. N atom and also hydrogen bonds in HF are symmetrical.

The difference in boiling or melting point, even after nearly the same molecular geometry, is because opf the presence of hydrogen bond. HF forms intermolecular hydrogen bonds due to fluorine's high electronegativity. This intermolecular hydrogen bonding requires more energy due to break the hydrogen bonds and melt or boil. So, stronger intermolecular forces of HF result in a higher boiling point.