Hey Clive, if you were to look up on the definition of hydrogen bonding, it says the molecule needs to have a hydrogen atom bonded to a very electronegativity atom(F,O or N) and not with Cl. This is very clearly seen in the boiling point of hydrogen halides. The abnormally high(and also it doesn't follow the general increase) B.p of HF is due to hydrogen bonding.
I have found the following articlehttp://www.chemguide.co.uk/atoms/bonding/hbond.html
This restates Astrokel's point that the b.pt. of HF is anomalous in relation to the other hydrogen halides. H2
O and NH3
both exhibit the same anomalous behaviour of b.pt. The explanation given for this anomalous behaviour is hydrogen bonding. The mechanism
of hydrogen bonding is explained as due to both
* The hydrogen is attached directly to one of the most electronegative elements, causing the hydrogen to acquire a significant amount of positive charge.
* Each of the elements to which the hydrogen is attached is not only significantly negative, but also has at least one "active" lone pair.
Lone pairs at the electron level 2 (CRL: period 2 elements: N, O and F) have the electrons contained in a relatively small volume of space which therefore has a high density of negative charge. Lone pairs at higher energy levels (CRL: for example chlorine) are more diffuse and not so attractive to positive things (CRL: such as H+).
Hence, only N, O and F have both properties therefore they are the only elements that can accept hydrogen bonds.
The article goes on to argue that Cl-
can be considered to accept a "weak form" of hydrogen bonding when Cl-
is hydrated in aqueous solution.