1. Chemical and Physical Changes

2. -TASTE (ONLY IF WE KNOW NOTHING IS POISONOUS)
PHYSICAL PROPERTIES
WE USE OUR SENSES:
-HEAR
-SEE
-TASTE (ONLY IF WE KNOW NOTHING IS POISONOUS)
-FEEL (ONLY IF WE KNOW NOTHING IS EXTREMELY ACIDIC OR EXTREMELY BASIC)
-SMELL (HOW DO WE CORRECTLY SMELL IN THE LAB?)
WE USE MEASURING DEVICES:
-MASS -TEMPERATURE
-CALCULATE DENSITY -DIMENSIONS
Physical properties can be determined without destroying the substance.

3. Chemical Properties
A chemical property describes the behavior of a substance as it becomes a new substance
-Flammability
-Combustion
-Corrosion
Tarnish
Rust
Reactivity
Oxidation
Chemical Property

4. Physical and Chemical Changes
We experience physical and chemical changes everyday when we cook an egg, burn gasoline in the car, freeze water to make ice cubes or mix vinegar and oil to make salad dressing.

5. Physical Change
A change in which the matter’s physical appearance is altered, but composition remains the same.
The same molecule is present throughout each stage.
Physical changes are related to the physical properties of the substance.

6. In a physical change, the substance involved remains the same.
Most physical changes are easy to reverse.
Physical Change
Description
Changes of State
e.g. Melting, Freezing, Boiling

7. Physical Change Dissolving solids into liquids
Description
Dissolving solids into liquids
e.g. dissolving salt (solute) into water (solvent), making Kool-Aid

8. Chemical Change
In a chemical change, the original substance is changed into one or more new substances.
The new substances have different properties from the original substance.
Most chemical changes are difficult to reverse.

9. Chemical Changes Examples: Bread baking Iron rusting Metal corroding
Frying an egg

10. Clues that a Chemical Change has occurred:
A new color appears.

11. Clues that a Chemical Change has occurred:
Heat or light is produced or absorbed.

12. Clues that a Chemical Change has occurred:
Bubbles of gas are formed.

13. Clues that a Chemical Change has occurred:
A solid material (a precipitate) forms in a liquid.