hydrogen bond NH3 , HCl

In formation of an intermolecular hydrogen bond, a partial dative bond is formed between the "bare proton" (i.e. the hydrogen atom with rather high partial positive charge) of a molecule and the lone pair of the very electronegative atom (F, N and O).

Cl is a period 3 element (with 3 filled electronic shells) while N atom is a period 2 element (with only 2 filled electronic shells). The size of Cl atom is much larger than that of N atom, and thus the electron clouds of the lone pair electrons on Cl atom are too diffused to form hydrogen bond. Therefore, N atom can form hydrogen bonds under suitable conditions (e.g. in pure NH3 liquid), but Cl cannot.
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