Question

Ortho-nitrophenol is steam volatile whereas para-nitrophenol is not. This is due to
$1.$Intramolecular hydrogen bonding present in ortho-nitrophenol
$2.$Intermolecular hydrogen bonding present in para-nitrophenol
$3.$Intramolecular hydrogen bonding present in para-nitrophenol
$4.$Inter-molecular hydrogen bonding present in ortho-nitrophenol.

• A. $1\&3$
• B. $1,3\&4$
• C. $1\&2$
• D. $2only$

Answer 1

The correct option is C $1\&2$

Para-nitro phenol has higher boiling point than ortho-nitrophenol due to intermolecular hydrogen bonding present in para-nitrophenol, which requires more energy to break these bonds during boiling. In o-nitrophenol, intramolecular hydrogen bonding is present to greater extent. Thus, o-nitrophenol is steam volatile due to low boiling point.