Rank the following compounds in order of increasing boiling

Rank the following compounds in order of increasing boiling point.

heptane

CH3CH2CH2CH2CH2CH2CH3

ethane

CH3CH3

butane

CH3CH2CH2CH3

pentane

CH3CH2CH2CH2CH3

propane

CH3CH2CH3

hexane

CH3CH2CH2CH2CH2CH3

Solution

The order of increasing boiling point: ethane < propane < butane < pentane < hexane < heptane

Explanation: The boiling point of alkanes increases as the carbon chain increases due to the increase in vanderwaal forces of attraction.