1. Physical and Chemical Change

2. Physical Change
Physical change: a change that occurs that does not change the identity of the substance
Some common physical changes include:
breaking
melting
freezing
dissolving
melting
tearing
boiling 2

3. Signs of a Physical Change
A physical change has occurred if it ONLY:
Changes size
Changes shape
Changes state of matter 3

4. Chemical Changes
Chemical change: a change that occurs causing the identity of the substance to change
In a chemical change where there is a chemical reaction, a new substance is formed and energy is either given off or absorbed.
burning
exploding
rusting
baking
toasting 4

5. Signs of a Chemical Change
If it ALSO:
Production of a gas (bubbles)
Changes temperature (without added heat/cooling source)
Forms a solid in a liquid - precipitate
Gives off light, heat, or electricity
Changes color
Reacts with Oxygen
Gives off a new odor 5

6. Logs burning

7. Water freezing

8. Fireworks

9. Sugar dissolving in tea

10. Baking a cake

11. Cutting paper

12. Crushing an aspirin

13. Lighter fluid burning

14. Mixing chemicals and a smell
is produced….

15. Rusting door

16. Boiling water

17. Erosion from wind

18. Painting a wall

19. Frying an egg

20. Bursting bubbles

21. Sour milk

22. Burning charcoal

23. Melting snowman

24. Digestion of food

25. Destruction of property by acid rain