You are correct! 2-methyl-1-butene actually has a *lower* boiling point than 1-pentene. Here's why:

Branching and Boiling Point

* Branching decreases boiling point: Branched alkanes have lower boiling points than their straight-chain isomers. This is because branching reduces the surface area available for intermolecular forces (like London dispersion forces) to act upon.

Comparing 2-methyl-1-butene and 1-pentene

* 1-pentene: A straight-chain alkene with a larger surface area.

* 2-methyl-1-butene: A branched alkene with a smaller surface area due to the methyl group branching off the main chain.

Conclusion

Since 1-pentene has a larger surface area, it experiences stronger intermolecular forces, requiring more energy to overcome these forces and transition to the gas phase. This results in a higher boiling point compared to 2-methyl-1-butene.

Let me know if you have any other questions!