1. Chemistry
Mrs. Algier
Do Now: Complete matter classification worksheet.

2. YWBAT Differentiate between physical and chemical properties.
Differentiate between physical and chemical changes.

3. Physical Property
Characteristic that can be observed or measured WITHOUT changing the substance’s composition
Examples
State (Solid, Liquid, Gas)
Color
Melting Point

4. Chemical Property
Chemical Property - Properties that can only be observed when we attempt to change the identity of a material
Example
The ability to rust is a chemical property of iron. Iron combines with oxygen to form rust.

5. Physical or Chemical Property?
Blue Color
Density
Flammability
Melting Point
Reacts with acid to form Hydrogen
Burns
Boiling Point
Hardness
Luster (shininess)
Odor

6. Chemical Property
Chemical Properties can be used to identify a substance…but chemical properties can only be observed when a substance undergoes a chemical change.
During a chemical change, the composition of matter always changes.

7. Charcoal
Break
Physical Change
Burn
Chemical Change

8. Chemical Changes A chemical change is also called a chemical reaction.
During a chemical reaction, one or more substances change into one or more new substances.
Reactant – a substance present at the start of the reaction
Product – a substance produced in the reaction

9. Signs of a Chemical Change
Transfer of energy
Color Change
Production of a gas
Precipitate Formation

10. Transfer of Energy Every chemical change involves a transfer of energy
Energy stored in natural gas is used to cook food.
The methane in the natural gas chemically combines with oxygen in the air.
Energy is given off in the form of heat and light.
Some of the energy is transferred to and absorbed by food.

11. Color Change
When a test strip is dipped in a solution, the color change is used to determine the pH of the solution.

12. Production of a Gas
Bubbles of carbon dioxide form when two antacid tablets are dropped into a glass of water.

13. Precipitate Formation
In the production of cheese, a reaction causes milk to separate into solid curds and liquid whey

14. Physical or Chemical Change?

15. Signs of a Chemical Change
If you observe a clue to chemical change, you cannot be certain that a chemical change has taken place. The clue may be the result of a physical change.
The only way to be sure that a chemical change has occurred is to test the composition of a sample before and after the change.

16. Law of Conservation of Mass
During any physical change or chemical reaction, the mass of the products is always equal to the mass of the reactants. Mass of Reactants = Mass of Products Mass is neither created nor destroyed.

17. Types of Changes Physical Change Chemical Change
Properties change, but the composition of the material does not change
Examples:
Changes of state (solid, liquid, gas)
Changes of size (break, split, grind, cut, crush)
Change that produces matter with a different composition
Examples:
Burning
Rusting
Oxidation

18. Physical or Chemical Change?
Photosynthesis
Sodium pellet sliced in two
Water heated to steam
Iron rusts
Sugar dissolves in water
Apple rots
Tire is inflated with air
Pancakes cook on a griddle
Food is digested in the stomach