1. Physical and Chemical Changes

2. What is a Physical Change?
A physical change alters the form of a substance, but does not change it to another substance.
Example:
Sawing Wood
Example:
Making Orange Juice

3. The three states of matter we will look at today are:
Solid
Liquid
Gas

4. When a solid changes to a liquid.
Changes of State
Melting
When a solid changes to a liquid.
Physical Change

5. When a liquid changes to a gas by heating.
Changes of State
Boiling
When a liquid changes to a gas by heating.
Physical Change

6. When a liquid changes to a gas with no heating.
Changes of State
Evaporation
When a liquid changes to a gas with no heating.
Physical Change

7. When a gas changes to a liquid.
Changes of State
Condensation
When a gas changes to a liquid.
Physical Change

8. When a liquid changes to a solid
Changes of State
Freezing
When a liquid changes to a solid
Physical Change

9. When a solid changes directly into a gas
Changes of State
Sublimation
When a solid changes directly into a gas
Physical Change

10. What is a Chemical Change?
When a substance undergoes a chemical change, it is changed into a different substance with different properties.
Example:
Rusting Metal
Example:
Baking a Cake

11. 5 Signs of a Chemical Change IT TAKES TWO!!!
Color Change
Precipitation

12. Precipitation
When solid forms from a solution during a chemical reaction.
It looks like a cloudy solid in an otherwise clear solution.

13. 5 Signs of a Chemical Change IT TAKES TWO!!!
Color Change
Precipitation
Gas Production
Temperature Change or Combustion
Changes in Characteristic Properties (odor, light given off)

14. 10 Really Cool Chemical Changes
Watch for the 5 signs!!!

15. Chemical or Physical Change?
Cutting paper?
Physical

16. Chemical or Physical Change?
Ice melting?
Physical

17. Chemical or Physical Change?
Toast burning?
Chemical

18. Chemical or Physical Change?
Disappearing puddle?
Physical

19. Chemical or Physical Change?
Rocket fuel burning?
Chemical

20. Chemical or Physical Change?
Candle burning?
Chemical

21. Chemical or Physical Change?
Dry ice?
Physical