1.  1. What are the types of pure substances?  2. What is the difference between an element and a compound?

2. UNIT 2 Matter and Change

3. Mixtures vs. Compounds All Matter Pure Substance ElementCompound Mixture - Made up of only 1 kind of matter - Has uniform and definite composition - simplest form - cannot be divided - 2 or more different elements chemically combined - 2 or more pure substances physically blended together

4. ElementCompound Mixture

5. Compounds vs Mixtures 1. Create a new form of matter with unique properties 2. Fixed/definite composition Ex: Aspirin is always 60% Carbon, 35.5% Oxygen and 4.5% Hydrogen. 3. Can only be separated be a chemical change Color, size, solubility, odor, density, freezing, melting, or boiling points 1. Combine properties of its parts Ex: Red + White = pink 2. Ratio between parts can vary Ex: Concrete may be 90% sand or 85% or even 1% 3. Can be separated by physical properties

6. Mixtures vs. Compounds All Matter Pure Substance Element Compound Mixture Homogenous Heterogenous

7.  Homogeneous Mixtures have a uniform composition throughout  Ex: gasoline, syrup, air and metal alloys like gold, steel or brass  Homogeneous mixtures are also called solutions

9.  Heterogeneous Mixtures are not uniform in composition  Ex: orange juice, chocolate chip cookies, lucky charms, Italian dressing, salads

10. Homogeneous or Heterogeneous?

11. Phases  A uniform part with the same properties  Since Homogeneous mixtures are uniform throughout they only have 1 part or phase  Heterogeneous mixtures have 2 or more distinct parts or phases

12. For separating liquids… use DISTILLATION For separating liquids from solids…use FILTRATION

13. Practice Pure Substance or Mixture? 1. Air 2. cobalt 3. Carbon Dioxide 4. Salt water 5. granite 6. Raisin Bran cereal

14. Practice Homogeneous or Heterogeneous? 1. Blood 2. Apple 3. Oil and water 4. Raisin Bran 5. Granite 6. Tea