(N/A) Hydrogen bonding is a special type of dipole-dipole attraction between a hydrogen atom covalently bonded to a highly electronegative atom (like $F$,$O$,or $N$) and another electronegative atom in the same or a different molecule.
$1$. Intermolecular Hydrogen Bonding:
- It occurs between two different molecules of the same or different compounds.
- Example: Liquid $HF$ or $H_2O$.
- Effect: It leads to association of molecules,resulting in higher melting and boiling points.
$2$. Intramolecular Hydrogen Bonding:
- It occurs when a hydrogen atom is bonded to a highly electronegative atom and is attracted to another electronegative atom present within the same molecule.
- Example: $o$-Nitrophenol.
- Effect: It results in chelation,which generally decreases the boiling point compared to its isomers due to reduced intermolecular association.