1. Phase Changes 09/23/2013 IN: (copy and complete the statements)
Solids have particles that are _________ _____________.
Liquids have an ____________ shape and a _______________ volume.
Gases have particles that are _________ ________________ and move _______.
Plasmas have so much energy added that the atoms split into _______ and ______ particles

2. Phase Changes
Objective: SWBAT use key vocabulary to describe matter changing from one state to another.

3. Changing from One State of Matter to Another
Phase Changes
Changing from One State of Matter to Another

4. Changing states
Matter can change from one state to another when energy is released or absorbed.
This is called a change of state or a phase change .

5. Phase changes Important things to know:
Phase changes occur because of the gain or loss of energy.
If energy is gained, molecules are moving faster.
If energy is lost, molecules are moving slower.
During a phase change, the temperature of a substance remains constant (flat/horizontal part of graph).

6. State Change Pyramid Gas Liquid Solid Absorbing Releasing
thermal energy
Releasing
thermal energy
Solid
Gas
Liquid

7. State Change Pyramid Gas Liquid Solid Melting Absorbing Releasing
energy
Releasing
energy
Gas
Melting
Liquid
Solid

8. Melting
The change from the solid state to the liquid state is melting.
The temperature at which a substance changes from a solid to a liquid is called the melting point.
Energy is absorbed during melting.

9. Brain Break: Gotch ya!

10. State Change Pyramid Gas Liquid Solid Melting Freezing Absorbing
thermal energy
Releasing
thermal energy
Gas
Melting
Freezing
Liquid
Solid

11. Freezing
The change from the liquid state to the solid state is called freezing.
The temperature at which a substance changes from the liquid state to the solid state is called the freezing point.
Energy is released during freezing.

12. State Change Pyramid Gas Liquid Solid Vaporization Melting Freezing
Absorbing
thermal energy
Releasing
thermal energy
Gas
Vaporization
Melting
Freezing
Liquid
Solid

13. Vaporization
The change from a liquid to a gas is known as vaporization.
The temperature of the substance does not change during vaporization.
However, the substance absorbs thermal energy.

14. State Change Pyramid Gas Liquid Solid Condensation Vaporization
Absorbing
thermal energy
Releasing
thermal energy
Gas
Condensation
Vaporization
Melting
Freezing
Liquid
Solid

15. Condensation As a gas cools, its particles slow down.
When particles move slowly enough for their attractions to bring them together, droplets of liquid form.
This process, which is the opposite of vaporization, is called condensation.

16. State Change Pyramid Gas Liquid Solid Condensation Sublimation
Absorbing
thermal energy
Releasing
thermal energy
Gas
Condensation
Sublimation
Vaporization
Melting
Freezing
Liquid
Solid

17. Sublimation
Some substances can change from the solid state to the gas state without ever becoming a liquid.
During this process, known as sublimation, the surface particles of the solid gain enough energy to become a gas.
Picture from

18. State Change Pyramid Gas Liquid Solid Deposition Condensation
Absorbing
thermal energy
Releasing
thermal energy
Gas
Deposition
Condensation
Sublimation
Vaporization
Melting
Freezing
Liquid
Solid

19. Deposition
When a substance changes from a gas to a solid without becoming a liquid, it is called deposition.
The gas particles lose energy very quickly in this process.
Deposition of water causes humid air to condense into frost patterns, for example in single-layer window glasses and windshields

20. Special phase changes for plasmas
Ionization:
When a gas is heated to the point that the atoms split into ions!
Remember: plasmas are made of positive ions and electrons.
Deionization:
When a plasma is cooled and the electrons and ions form back into atoms.