Question

The correct order of boiling points of the compounds given below is 
[A)] Methoxy ethane 
[B)] Propan-1-ol 
[C)] Propanal 
[D)] Propanone

• A. C > B > A > D
• B. B > D > C > A
• C. B > C > D > A
• D. C > A > B > D

Hint:

Hydrogen bonding significantly increases boiling points. Alcohols boil higher than ketones, which boil higher than aldehydes and ethers.

Answer 1

The Correct Option is B

Step 1: Evaluate intermolecular forces. Propan-1-ol (B) exhibits hydrogen bonding — strongest intermolecular force.
Propanone (D) has dipole-dipole interactions due to the carbonyl group.
Propanal (C) also has dipole-dipole interactions, slightly weaker than ketones.
Methoxy ethane (A) is an ether with only weak dipole interactions — lowest boiling point.
Step 2: Compare boiling points based on the strength of interactions: \[ \text{Propan-1-ol} > \text{Propanone} > \text{Propanal} > \text{Methoxy ethane} \] Thus, the correct order is: B > D > C > A