1. Section 2.2 Properties of Matter
Objectives/ Goals:
1. To learn to distinguish between physical and chemical properties
2. To learn to distinguish between physical and chemical changes

2. A. Physical & Chemical Properties and Changes
Physical Property:
Characteristic of a substance that can change without the substance becoming a new/different substance
Ex: odor, color, volume, density, state (solid, liquid, gas), melting point

3. Chemical Property:
Characteristic that describes the ability of a substance to change to a different substance
Ex: wood burning, rusting of steel, digestion of food

4. Practice:
Classify each of the following as a physical or a chemical property
A. The boiling point of a certain alcohol is 78
B. Diamonds are very hard
C. Sugar ferments to form alcohol
D. A metal wire conducts an electric current

5. More practice... 1. Ice melts at 0 2. Propane burns in the air
3. Lead is a very dense metal
4. Leaves turn colors in the fall

6. Physical Changes
Change that does NOT affect the composition of a substance
* A change in one or more physical properties, but NO change in the components that make up that substance
Most common:

7. Chemical Change
Change in which a substance becomes a different substance
*Involves a change in the components of the substance; a given substance changes into a different substance(s)
A plant forms a leaf by combining various substances from the air and soil, silver tarnishes by reacting with substances in the air

8. Practice w/ Physical or Chemical CHANGES
1. You make scrambled eggs
2. You step on a piece of chalk and it becomes powdered
3. You light a candle when the electricity goes out
4. Steam from your hot shower condenses on a cold mirror
5. Iron metal is melted