Question

Ortho-nitrophenol is less soluble in water than p- and m- nitrophenols because:

• A. o-nitrophenol shows intramolecular H- bonding.
• B. o-nitrophenol shows intermolecular H- bonding.
• C. melting point of o-nitrophenol is lower than those of m- and p- isomers.
• D. o-nitrophenol is more volatile in steam than those of m- and p- isomers.

Answer 1

Answer: (A)

o-nitrophenol shows intramolecular H- bonding.

Due to intramolecular H-bonding, $-OH$ group is not available to form a hydrogen bond with water. Hence o-nitrophenol is sparingly soluble in water while m- and p-nitrophenol are soluble due to intermolecular H-bonding with water.