Question

Arrange the compounds in the order of decreasing boiling points.
1. Butane
2. 1,2,3-Pentane triol
3. Butyl alcohol

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

Answer 1

The correct option is A $2>3>1$

The decreasing order of boiling point is:
1,2,3-Pentane triol > Butyl alcohol > Butane

In (2), there is presence of three alcohol groups, so it has more H-bonding than in (3). So (2) has more boiling point than (3). (1) has the least boiling point, because it has no alcohol group.