It is an attractive force between the covalently bonded H-atom of one molecule and an electronegative atom such as F, O, or N of another molecule. A hydrogen bond is merely a strong electrostatic attractive force and not a normal chemical bond. It is very weak as compared to a covalent bond and is represented by a dotted line.
Types of Hydrogen Bond:
There are mainly two types of Hydrogen Bond:
1. Inter-molecular: It occurs between different molecules, such as H2O, HF, etc.
2. Intra-molecular: It occurs within two atoms of the same molecules, such as Salicylaldehyde, ortho Nitrophenol, etc.