Question

What effect does branching of an alkane chain has on its boiling point?

Answer 1

Boiling points of alkanes

• The boiling points of alkanes rise as the number of carbons increases.
• Since nonane has a longer carbon chain than octane, it will have a higher boiling point.

Effect of branching on the boiling point of alkane

• As an alkane chain branch, the surface area of the molecule decreases.
• The intermolecular force reduces as a result of this.
• At a lower temperature, the forces can be readily overcome.
• Therefore, as the branching increases, the boiling point of an alkane chain decreases.