A phase change is the reversible physical change that takes place when a substance changes from one state to another
_______________________________________________________________________________________________________________________________________________________________________________________
Types of phase changes
Freezing - liquid to solid
Melting - solid to liquid
Vaporization (boiling) - liquid to gas
Condenstion- gas to liquid
Sublimation- solid to gas
Depostion- gas to solid
_______________________________________________________________________________________________________________________________________________________________________________________
The tempature during a phase change remains constant (doesnt change)
During a phase change it is either
absorbing energy
-OR-
releasing energy
_______________________________________________________________________________________________________________________________________________________________________________________
Endothermic: Internal heat (adding heat/energy)
-ex. Melting ice cubes, Boiling water
Exothermic: External heat (removing heat/energy)
-ex. freezing ice cubs, burning sugar
_______________________________________________________________________________________________________________________________________________________________________________________
VAPORIZATION
Evaporation
- Vaporization is the phase change
- at the surface of a liquid
- below the boiling point of a liquid (takes longer)
Boiling
- Vaporization is the phase change
- throughout the liquid
- at the boilding point of a liquid (quicker)