Question

Which of the following isomers is more volatile: $o$-nitrophenol or $p$-nitrophenol?

Answer 1

o-nitrophenol is more volatile than p-nitrophenol.
o-nitrophenol involves intramolecular hydrogen bonding and p-nitrophenol involves inter molecular hydrogen bonding.
Intermolecular hydrogen bonding leads to association of several molecules of p nitrophenol which results in high boiling point and less volatile nature.