1. Physical and Chemical Changes

2. Properties of Matter
All pure substances have characteristic properties
Properties are used to distinguish between substances
Properties are also used to separate substances

3. Physical Properties
A Physical Property is a characteristic that can be observed or measured without changing the composition of the substance
Physical properties describe the substance itself
Examples
Physical State
Color
Mass, shape, length
Magnetic properties

4. States of Matter
There are three common states of matter: solid, liquid, and gas

5. Solids Definite shape and definite volume
Particles are packed tightly together and held in fixed positions
Particles vibrate about fixed points

6. Liquids Definite volume Takes the shape of its container
Example: Milk in a glass vs. Milk in a gallon jug
Particles can move past each other (fluid)
Fluid – Anything that can be poured
Particles move more rapidly than in a solid

7. Gases No definite shape, takes the shape of its container
No definite volume
Particles are spread far apart and move past each other rapidly

8. Chemical Properties
A Chemical Property indicates how a substance will react with another
Chemical properties cannot be determined without changing the identity of the substance
Examples:
Iron Rusting
Silver Tarnishing

9. Physical Changes
A Physical Change is a change in a substance that does not alter the substance’s identity
Examples:
Grinding
Cutting
Mixing
ALL CHANGES OF STATE ARE PHYSICAL CHANGES!!

10. Changes of State Melting – solid becomes a liquid
Freezing – liquid becomes a solid
Melting and Freezing Points are the SAME TEMPERATURE

11. Changes of State Condensation – gas becomes a liquid
Boiling – liquid becomes a gas
Condensation and Boiling Points are the SAME TEMPERATURE

12. Changes of State Sublimation – solid becomes a gas
Example: dry ice
Deposition – gas becomes a solid

13. Chemical Changes
A change in which one or more substances are converted into different substances is called a Chemical Change
Signs of a Chemical Change:
Color Change
Gas is Released
Temperature Change
Precipitate – Solid falls out of solution
Substance Disappears

14. Intensive vs. Extensive Properties
Extensive properties depend on the amount of matter that is present
Examples: Energy in a substance, Volume, Mass
Intensive properties do not depend on the amount of matter present
Examples: Density, Melting Point, Boiling Point

15. Qualitative vs. Quantitative Measurements
Qualitative measurements are descriptive
Examples:
Physical State, Color, Shape, Sound, Smell
Quantitative measurements are numerical
Length, Mass, Volume, Density