1.
Phase Changes <ul><li>A reversible physical change that occurs when a substance changes its state, solid, liquid or gas </li></ul><ul><li>Melting, Freezing, vaporization, condensation, sublimation, and deposition are six common phase changes </li></ul>

2.
Temperature and phase changes <ul><li>The temperature of a substance does not change during a phase change. </li></ul><ul><li>Freezing and melting points are the same temperature </li></ul><ul><li>Vaporization and Condensation points are the same </li></ul>

3.
Energy and Phase Change <ul><li>Energy is either absorbed or released during a phase change </li></ul><ul><li>Endothermic change absorbs energy (Melting) </li></ul><ul><li>Exothermic change releases energy into surroundings (freezing) </li></ul><ul><li>Heat of fusion is the amount of energy something absorbs in order to melt </li></ul>

4.
Melting and Freezing <ul><li>The arrangement of molecules become more orderly as a substance freezes (becomes solid), and less orderly as something melts (becomes liquid). </li></ul>

5.
Vaporization and Condensation <ul><li>Vaporization is an endothermic phase change of a liquid to a gas </li></ul><ul><li>The amount of energy it takes to cause a substance to go from a solid to a liquid is called the heat of vaporization </li></ul>

6.
Two types of Vaporization <ul><li>Evaporation- Takes place at the surface of a liquid (occurs below boiling). </li></ul><ul><li>Vapor pressure is caused by the collision of particles with the walls of a container </li></ul><ul><li>Boiling- when vapor pressure becomes equal to the atmospheric pressure substances boil </li></ul>

7.
Condensation <ul><li>Condensation is when a substance turns from a gas to liquid. </li></ul><ul><li>EX. include dew, water on the outside of a glass of lemonade on a hot day. </li></ul>

8.
Sublimation and Deposition <ul><li>Sublimation is a phase change in which a solid goes directly to a gas </li></ul><ul><li>(Dry Ice) </li></ul><ul><li>Deposition is a phase change in which a gas becomes a solid </li></ul><ul><li>(Frost) </li></ul>