Question

Why does pentane have a higher boiling point than dimethylpropane?

A) Pentane has a larger molecular size and greater surface area.

B) Pentane has stronger London dispersion forces than dimethylpropane.

C) Dimethylpropane has stronger hydrogen bonding interactions.

D) Pentane has a higher molar mass and more complex molecular structure.

Answer 1

Pentane has a higher boiling point than dimethylpropane mainly because of its larger molecular size and greater surface area that increase London dispersion forces.

Step-by-step explanation:

The reason pentane has a higher boiling point than dimethylpropane is due to two main factors: molecular size and surface area. Pentane has a larger molecular size and a more extended shape that allows for more substantial London dispersion forces. In contrast, dimethylpropane (also known as neopentane) is almost spherical with a smaller surface area, leading to weaker intermolecular interactions and a lower boiling point. The larger surface area of pentane molecules means that they can interact more effectively with each other compared to the relatively spherical dimethylpropane molecules, resulting in a higher boiling point for pentane.