1. Physical and Chemical Changes

2. Physical Changes Physical changes- A change that affects one or more physical properties of a substance but does not change the chemical identity of the substance. If you melt a block of ice, you still have H2O at the end of the change. 

3. Physical Changes
Any change in size, shape, form, or state where the identity of the matter stays the same
Example:
cutting a watermelon into slices
tearing up a sheet of paper
sharpening a pencil
Often easy to reverse with:
filtration, magnetism, evaporation, distillation and centrifuge (spinning)

4. Physical Change Signs that a physical change is taking place
Change in Appearance
Change in state of matter
Observed without doing anything
Measured quantity
Key words to look for
Melts
Evaporates
Bent
Conductor

5. Physical Changes Some common examples of physical changes are: melting, freezing, condensing, breaking, crushing, cutting, and bending.

6. Chemical Changes Chemical changes, or chemical reactions, are changes that result in the production of another substance. 

7. Chemical Changes
Signs that a chemical change (reaction) is taking place
Bubbles form
Odor released/ forms
Fizzing occurs
Something burns
A gas is released
Heat produced
Light produced
Precipitate (solid) forms
Rusting occurs
A color change occurs
Key words to look for
Burning
Reacts
Bubbles
Tarnishes
Explodes
Heats up
Sours

8. Physical or Chemical Change?
Painting Wood
PHYSICAL

9. Physical or Chemical Change?
Burning Paper
CHEMICAL

10. Physical or Chemical Change?
Digestion of food
CHEMICAL

11. Sugar dissolving in water PHYSICAL
Physical or Chemical Change?
Sugar dissolving in water
PHYSICAL

12. Iron turning red when heated PHYSICAL
Physical or Chemical Change?
Iron turning red when heated
PHYSICAL

13. Physical or Chemical Change?
Evaporation
PHYSICAL

14. A pond freezing in winter PHYSICAL
Physical or Chemical Change?
A pond freezing in winter
PHYSICAL

15. Physical or Chemical Change?
Melting ice
PHYSICAL

16. Physical or Chemical Change?
Cutting wire
PHYSICAL

17. Physical or Chemical Change?
Painting fingernails
PHYSICAL

18. Physical or Chemical Change?
Cutting fabric
PHYSICAL

19. Physical or Chemical Change?
Baking muffins
CHEMICAL

20. Physical or Chemical Change?
Shattering glass
PHYSICAL

21. Decomposition of old leaves CHEMICAL
Physical or Chemical Change?
Decomposition of old leaves
CHEMICAL

22. Physical or Chemical Change?
Wrinkling a shirt
PHYSICAL

23. Physical or Chemical Change?
An old nail rusting
CHEMICAL