Condition for Effective Hydrogen Bonding - QS Study
QS Study

Hydrogen bonding comes into existence as a result of dipole-dipole interactions between the molecule in which hydrogen atom is covalently bonded to a highly electronegative atom.

Therefore, the conditions for the effective hydrogen bonding are:

(i) high electro negativity of the atom bonded to hydrogen atom so that bond is sufficiently polar.

(ii) small size of the atom bonded to hydrogen so that it is able to attract the bonding electron pair effectively.

If the atom bonded to hydrogen has low value of electro negativity and/or large atomic size, dipole-dipole interactions are not strong enough to allow effective hydrogen bonding.

Only nitrogen, oxygen and fluorine form strong hydrogen bonds because they have high value of electro negativity and small atomic size.