Final answer:
Hydrogen bonds are very strong compared to other dipole-dipole interactions, but weaker than a covalent bond. The strength of hydrogen bonds is attributed to the high electronegativity of the elements involved.
Step-by-step explanation:
A hydrogen bond is an intermolecular attractive force in which a hydrogen atom, that is covalently bonded to a small, highly electronegative atom, is attracted to a lone pair of electrons on an atom in a neighboring molecule. Hydrogen bonds are very strong compared to other dipole-dipole interactions, but still much weaker than a covalent bond. A typical hydrogen bond is about 5% as strong as a covalent bond.
The strength of hydrogen bonds can be attributed to the high electronegativity of the elements involved. Electronegativity is a measure of an atom's ability to attract electrons towards itself. In the case of hydrogen bonds, the highly electronegative atoms (such as oxygen, nitrogen, and fluorine) attract the shared electrons in the covalent bond more strongly, creating a partial positive charge on the hydrogen atom. This partial positive charge then attracts the lone pair of electrons on a neighboring molecule, resulting in a strong electrostatic interaction called a hydrogen bond.