Question

how do compounds separate based on their boiling points during fractional distillation? high boiling point compounds vaporize first, collect at top; low boiling point ones stay near bottom low boiling point compounds vaporize first, collect at top; high boiling point ones stay near bottom compounds separate only after all have vaporized and condensed

Explanation:

Fractional distillation separates mixtures based on boiling points. Lower - boiling compounds vaporize more easily. As the mixture is heated, low - boiling point compounds turn into vapor first. These vapors rise (since they are less dense in vapor form) and are collected at the top of the distillation column. High - boiling point compounds require more heat to vaporize and thus stay near the bottom until the temperature is high enough for them to vaporize.

Answer:

Low boiling point compounds vaporize first, collect at top; high boiling point ones stay near bottom.