Phase changes | Middle school chemistry | Khan Academy

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Phase changes are physical changes in which a substance shifts from one state of matter to another, like ice melting into water or water boiling into steam. These transformations depend on two factors: particle attractions and kinetic energy. Heating a substance increases particle motion, potentially overcoming attractions to change phases. Each substance has unique melting, freezing, and boiling points due to these forces.

00:00 Intro
00:22 What keeps particles together? (Attraction)
01:03 What makes them separate? (Kinetic energy)
2:00 Melting and melting point
3:43 Boiling and boiling point
4:35 Condensation and freezing
5:46 Why different substances have different melting & boiling points
6:55 Summary

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