The occur when a compound makes a transition between two of the following: A solid, a liquid, or a gas. They are all physical changes, as the composition of the material is unchanged.
These phase transitions are as follows:
- Melting: Solid to liquid
- Freezing: Liquid to solid
- Vaporizing: Liquid to gas
- Condensing: Gas to liquid
- Subliming: Solid to gas
- Deposition: Gas to solid
Of course, there are other physical changes that you can perform as well. For example, if you hit a window with a brick, the window will shatter, which is also a physical change.
OK.
