Question

Give reasons :
o-nitrophenol is more volatile than p-nitrophenol

Answer 1

Solution:-

Ortho-Nitrophenol forms intramolecular $H$-bond whereas molecules of para-Nitrophenol get associated through intermolecular $H$-bond. During boiling, the strong intermolecular $H$-bonding increases the boiling point but intramolecular $H$-bonding cannot do so.

Hence ortho-Nitrophenol is more volatile than para-Nitrophenol.