What happens to liquids with higher boiling points during fractional distillation?

During fractional distillation, liquids with higher boiling points undergo a specific behavior based on their physical properties. As the mixture is heated, the component liquids are separated based on their boiling points.

Liquids with higher boiling points do not vaporize as readily as those with lower boiling points; therefore, they remain in the distillation column or condense back into liquid form as the vapor rises through the column. The higher boiling point liquids will condense at higher levels within the column, depending on the temperature gradient, and some may return to the flask for further separation. This process allows for the refinement of the mixture, as lower boiling point substances can vaporize and be collected as they escape the column before the higher boiling point liquids.

This behavior explains why the answer is correct: during fractional distillation, higher boiling point liquids condense and return down the column instead of being collected early or evaporating completely. The meticulous temperature control in the column facilitates the ongoing separation of components.