Rank the following alkanes in order of decreasing boiling point, putting the alkane with the highest boiling point first.

Question

Quizplus · Accepted Answer

Boiling point of alkanes increases with increasing chain length due to more van der Waals forces. Both I and III have six carbon atoms, but I has more branches compared to III which makes its molecules more compact, so it has a higher boiling point. II has only four carbon atoms, so it has the lowest boiling point. Therefore, the correct order is I > III > II.

Rank the Following Alkanes in Order of Decreasing Boiling Point