1. Mixtures

2. Matter SubstancesMixtures Elements Compounds Heterogeneous Mixtures Homogeneous Mixtures Mixtures  Substances separated by physical methods Compounds  Substances separated by chemical methods

3. Mixtures Combo of 2 or more pure substances Physically combined NOT chemically combined Each substance retains its own identity and properties

4. Mixtures Variable composition No unique properties Ex: sugar and sand mixed together physical methodsSeparated by physical methods May be homogeneous or heterogeneous

5. Types of Mixtures Heterogeneous: See boundary or regions that look different Ex: colloids suspensions ice water granite cereals

6. Colloid: milk Suspension: smoke/smog Heterogeneous mixture: ice water Heterogeneous mixtures: cereal/granite

7. Homogeneous: constant composition throughout, single phase Ex: Solutions (all 3 phases) Air Windex kool-aid

8. Air Homogeneous Solutions: Drink mix Window cleaner

9. Hints for Mixtures Solutions (gas & liquid phases) transmit light No particles big enough to scatter light Look translucent (see-through) Suspensions look cloudy – scatter light Particles big enough to scatter light Settle upon standing

10. Where does this liquid fit? Homogeneous? Heterogeneous?

11. Particle Diagrams             Atoms only: monatomic element Molecules: diatomic element

12. Particle Diagrams                    Molecules: triatomic compound Mixture: monatomic element diatomic element triatomic compound   

13. Conservation of Mass Mass before = Mass after # atoms before = # atoms after

14. Separating Mixtures Physically combined Separation based on physical properties –Sorting: Appearance –Filtration: Size –Distillation: Boiling Point –Crystallization: Solubility –Magnet: Magnetization –Chromatography: “Travel” ability

15. Filter: Solid particles can be separated from liquid

16. Distillation Used to separate liquids with different boiling points

17. Paper Chromatograhy Can separate liquids with different solubilities

18. Crystallization Can separate solids dissolved in liquids