Question

Which one of the following is steam volatile?

• A. $o$ - nitrophenol
• B. Aniline
• C. Glycerol
• D. $p$ - nitrophenol

Answer 1

The correct option is A $o$ - nitrophenol

Due to intramolecular $H$-bonding, molecules have weak intermolecular force of attraction between them. Thus, they have low boiling. Hence, $o$-nitrophenol is steam-volatile.

Whereas aniline, glycerol and $p$-nitrophenol have intermolecular $H$-bonding which increase the attraction between the molecule i.e they have a higher boiling point.