Physical & Chemical Changes

1. Physical & Chemical Changes Is melted butter still butter? Is soured milk still milk? Are the ashes from a fire made of the same “stuff” as wood? 7 th Grade Brandy Butcher

2. What is a physical change? Change that affects one or more physical properties of a substance A new substance is not formed The substance keeps its identity (name)

3. Examples of Physical Change Any state change Melting Freezing Evaporating Dissolving Cutting Bending

4. Examples of Physical Changes in Nature Water Cycle Erosion

5. Can you think of any examples?

6. What is a chemical change? One or more substances are changed into a new substance New and different properties New identity (name)

7. Examples of a Chemical Change Cooking Burning Rusting

8. Examples of Chemical Changes in Nature Carbon Cycle Nitrogen Cycle Chemical Weathering

9. Can you think of any examples?

10. What are the signs a chemical change is happening? Change in color Change in odor Production of heat Production of fizzing, foam, bubbles Production of sound Production of light

11. What signs do this changes demonstrate? Light/Sound/Heat Light/Sound/Heat Change in odor and color Change in color Change in odor and color

12. Physical or Chemical Change? Frying an egg? Physical or Chemical

13. Incorrect. Try again!

14. Correct! Try the next one!

15. Physical or Chemical Change? Souring Milk? Physical or Chemical

16. Incorrect. Try again!

17. Correct! Try the next one !

18. Physical or Chemical Change? Shredding paper? Physical or Chemical

19. Incorrect. Try again!

20. Correct!

21. Credits All pictures used were free and retrieved from www.morguefile.com .