Question

Ammonia has a higher boiling point than phosphene why
1m question

Answer 1

NH3 exhibits hydrogen bonding in addition to dispersion forces. This significantly increases the intermolecular force, and raises the boiling point. PH3 does not exhibit hydrogen bonding and the dominant intermolecular force holding these molecules together is dispersion forces.

Hydrogen bonding takes more energy to break than dispersion forces and therefore gives ammonia the higher boiling point.