How does hydrogen bonding affect boiling points?

Hydrogen bonding significantly increases boiling points due to the strong attractive forces between molecules that contain hydrogen bonded to highly electronegative atoms such as nitrogen, oxygen, or fluorine. These electronegative atoms create a partial negative charge, while hydrogen, being less electronegative, acquires a partial positive charge. This results in a strong dipole-dipole interaction, known as hydrogen bonding.

When a substance has hydrogen bonds, a considerable amount of energy is required to overcome these intermolecular forces during the phase transition from liquid to gas, which corresponds to boiling. For example, water has a much higher boiling point compared to other molecules of similar molar mass because of the extensive hydrogen bonding present in its structure.

In contrast, substances without hydrogen bonding or with weaker intermolecular forces, like van der Waals forces, generally possess lower boiling points because they require less energy to transition to the gas phase. Thus, the presence of hydrogen bonding dramatically increases boiling points, making the option indicating a significant increase the most accurate in this context.