Explain why,in spite of having nearly the same electronegativity,oxygen forms hydrogen bonding while chlorine does not.

(N/A) Both chlorine and oxygen have almost the same electronegativity values ($3.44$ for $O$ and $3.16$ for $Cl$),but chlorine rarely forms hydrogen bonding. This is because,in comparison to chlorine,oxygen has a much smaller atomic size. As a result,oxygen has a higher electron density per unit volume,which allows it to exert a stronger electrostatic attraction on the hydrogen atom of another molecule,facilitating the formation of hydrogen bonds.