Which compound would have the highest boiling point among the following?

The compound with the highest boiling point is decane due to its larger molecular structure and greater intermolecular forces. As the carbon chain length increases, the surface area of the molecule also increases; this allows for a greater number of van der Waals (London dispersion) forces to operate between the molecules.

In the case of decane, it contains a total of ten carbon atoms and twenty-two hydrogen atoms, which results in a more significant amount of van der Waals interactions compared to shorter-chain hydrocarbons like propane, hexane, or octane. This leads to a higher boiling point because more energy (heat) is required to overcome these intermolecular forces to transition the compound from a liquid to a gas phase.

In summary, the increase in chain length correlates with an increase in boiling point due to intensified van der Waals forces among larger molecules, making decane the compound with the highest boiling point among the given options.