1. Physical and Chemical Changes
Video

2. Warm Up 2/5/17 Balance the following equation: 2Fe2O3 + C  Fe + 3CO2
Underline the coefficients and circle the subscripts
Put a Box around the reactants
Are there any elements? Which ones?
Is there any compounds? Which ones?
How many total atoms in your products?

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

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

5. 5 Signs of a Chemical Change
Color Change
Precipitation

6. Precipitation
Precipitation – the solid that forms from a solution during a chemical reaction.
It looks like a cloudy solid in an otherwise clear solution.

7. 5 Signs of a Chemical Change
Gas Production
Temperature Change

8. 5 Signs of a Chemical Change
Changes in Characteristic Properties (odor, light given off)

9. Chemical or Physical Change?
Cutting paper?
Physical

10. Chemical or Physical Change?
Ice melting?
Physical

11. Chemical or Physical Change?
Toast burning?
Chemical

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

13. Chemical or Physical Change?
Sawing wood?
Physical

14. Chemical or Physical Change?
Metal rusting?
Chemical

15. Chemical or Physical Change?
Disappearing puddle?
Physical

16. Chemical or Physical Change?
Candle burning?
Chemical

17. Chemical or Physical Change?
Dry ice?
Physical

18. Summary Physical Changes Chemical Changes -Crushing a can -Melting
-Boiling
-Mixing sand and water
-Breaking a glass
-Dissolving sugar and water
-Shredding paper
-Chopping wood
-Mixing red and green marbles
-Sublimation of dry ice
-Rusting of Iron
-Bubbling/fizzing
-Change in Temperature
-Combustion (burning wood)
-Metabolism (break down food in the body)
-Mixing an acid and a base
-Cooking (an egg)
-Digesting sugar (amylase in saliva)
-Explosion (the origin of it)
-Rotting bananas