1. Physical and Chemical Changes

2. Physical Change
Physical change- substance changes without forming a new substance.
Ex. Pour melted chocolate on ice cream.
It still tastes the same because the particles have not changed, it just hardened (changed state) because the ice cream was cool.

3. Chemical Change
Chemical Change- Always results in the formation of a new substance or substance
Examples:
Burning, Cooking, Rusting…
The formation of water from hydrogen and oxygen.

4. Chemical Change Clues A new colour appears.
Heat or light is given off.
Bubbles of gas are given off.
A solid material (called a precipitate) forms in a liquid.
The change is difficult to reverse.

5. Chemical or physical change?
Frying an egg?
Chemical change
New colour appears
Difficult to reverse

6. Chemical or Physical Change
Ice cubes melting
Physical Change
Change of State
only
It is still WATER

7. Chemical or Physical Change
Baking cookies?
CHEMICAL
Change
New Substance
Difficult to reverse

8. Chemical or Physical Crumpling a piece of paper Physical Change
STILL PAPER
Form has only changed

9. Physical or Chemical Bread moulding CHEMICAL CHANGE New substance
Change in Colour
Can not reverse

10. Physical or Chemical Apple turning brown CHEMICAL CHANGE New substance
Change in colour

11. Physical or Chemical
Formation or rain
PHYSICAL
CHANGE
Still Water

12. Physical or Chemical
Iron rusting
CHEMICAL
CHANGE
-Colour change

13. Physical or Chemical
Boiling water
PHYSICAL
Change
-still
WATER

14. Physical or Chemical Cutting diamonds PHYSICAL CHANGE
They are still diamonds