1. DO NOW Give an example of a physical and chemical change Physical Change 1. 2. Chemical Change 1. 2.

2. Objective: Content: I will analyze a time/temperature graph of a phase change experiment to determine the temperature at which the phase change occurs (freezing point, melting point, or boiling point). Language: I will write the definitions for phase changes in matter.

3. PHASE CHANGES Description of Phase Change Term for Phase Change Heat Movement During Phase Change Solid to liquid Melting Heat goes into the solid as it melts. Liquid to solid Freezing Heat leaves the liquid as it freezes.

4. PHASE CHANGES Description of Phase Change Term for Phase Change Heat Movement During Phase Change Liquid to gas Vaporization, which includes boiling and evaporation Heat goes into the liquid as it vaporizes. Gas to liquid Condensation Heat leaves the gas as it condenses. Solid to gas Sublimation Heat goes into the solid as it sublimates.

5. Review: 3 Phases of Matter Solid Liquid Gas

6. What is a Phase Change?Phase Change Is a change from one state of matter (solid, liquid, gas) to another. Phase changes are physical changes because: - It only affects physical appearance, not chemical make-up. - Reversible

7. What happens during a phase change? During a phase change, heat energy is either absorbed or released. Heat energy is released as molecules slow down and move closer together. Heat energy is absorbed as molecules speed up and expand.

8. Types of Phase Changes

9. Melting Phase change from a solid to a liquid Molecules speed up, move farther apart, and absorb heat energy

10. Freezing Phase Change from a liquid to a solid Molecule slow down, move closer together and release heat energy.

11. Vaporization (Boiling) Phase change from a liquid to gas. It occurs at the boiling point of matter. Molecules speed up, move farther apart, and absorb heat energy.

12. Evaporation Phase change from a liquid to a gas on the surface of a liquid (occurs at all temperatures). Molecules speed up, move farther apart, and absorb heat energy.

13. Condensation Phase change from a gas to a liquid. Molecule slow down, move closer together and release heat energy.

14. Sublimation Phase change from a solid to a gas. Molecules speed up, move farther apart, and absorb heat energy.

15. Deposition Phase change from a gas to a solid. Molecules slow down, move closer together and release heat energy.

16. Phase Changes of Matter Concept Map

17. Graphing a Phase Change

19. Melting & Boiling Points Melting Point: The temperature at which a solid changes into a liquid. Boiling Point: The temperature at which a liquid changes into a gas. What is a Freezing point? Compare the freezing and melting points of water.

20. Summary

21. Graphing a Phase Change – Why is there no change in temperature during a phase change? – Define melting and boiling points. – What is the melting point and boiling point of water? – At what temperature does water freeze and become a solid?