The order of the boiling point is H2O > NH3 > HCl. The extent of Hydrogen bonding is H2O > NH3 > HCl. Each water molecule can potentially form “four” hydrogen bonds with surrounding water molecules. There are exactly the right numbers of hydrogens and lone pairs so that every one of them can be involved in hydrogen bonding. Ammonia could form only “three” hydrogen bond per molecule. So, due to strong hydrogen bonds, more energy (heat) is required to boil water. Due high electronegativity of nitrogen then chlorine, bond between N-H is stronger than bond between H-Cl. That is why boiling point of NH3 is more than HCl.
