Question

Arrange the following alcohols in the decreasing order of their boiling points.
1. n-Butyl alcohol
2. sec-Butyl alcohol
3. tert- Butyl alcohol

• A. 1>2>3
• B. 1>3>2
• C. 2>1>3
• D. 3>2>1

Answer 1

The correct option is A 1>2>3

The decreasing order of boiling points is:
n-Butyl alcohol > sec-Butyl alcohol > t-Butyl alcohol

All alcohols have H-bonding, but alcohol (1) has more surface area. Alcohol (2) has less surface area due to branching, and alcohol (3) has more branching and less surface area than in alcohol (2). Hence the boiling point order is as given above.