Explain why inspite of nearly the same electronegativity, nitrogen forms hydrogen bonding while chlorine does not.

Explanation

Although O and Cl have nearly the same electronegativity, yet their atomic sizes are different. Atomic size of O is much less than that of Cl. As such, electron density per unit volume on oxygen atom is much higher than that on chlorine atom. Therefore, oxygen forms hydrogen bonds while chlorine does not even though both have nearly the same electronegativity.