Given below are two statements :
Statements I: o- Nitrophenol is steam volatile due to intramolecular hydrogen bonding.
Statement II: o- Nitrophenol has high meliting due to hydrogen bonding.
In the light of the above statements, choose the most appropriate answer from the options given below :
Statements I: o- Nitrophenol is steam volatile due to intramolecular hydrogen bonding.
Statement II: o- Nitrophenol has high meliting due to hydrogen bonding.
In the light of the above statements, choose the most appropriate answer from the options given below :
- (A)Statement I is false but Statement II is true
- (B)Both Statement I and Statement II are true
- (C)Both Statement I and Statement II are false
- (D)Statement I is true but Statement II is false✓ Correct
Answer: (D)
Solution
In o-nitrophenol the nitro group stands next to the hydroxyl group and the two close into a six membered chelate ring through an intramolecular hydrogen bond. The hydroxyl hydrogen is then locked inside the molecule and is not available to bind neighbouring molecules, so the forces between molecules stay weak and the compound passes over readily with steam. Statement I is true.
That same chelation is what keeps the molecules from associating, and a solid built of weakly held molecules melts low: o-nitrophenol melts at K, while p-nitrophenol, whose hydrogen bonding runs from one molecule to the next, melts at K. Statement II is false.
Statement I is true and Statement II is false.
That same chelation is what keeps the molecules from associating, and a solid built of weakly held molecules melts low: o-nitrophenol melts at K, while p-nitrophenol, whose hydrogen bonding runs from one molecule to the next, melts at K. Statement II is false.
Statement I is true and Statement II is false.
JEE Main · 2021 · 26 Feb 2021 · Shift 1 · Single correct option