Unit 1 thus far…

1. Unit 1 thus far… • What we have discussed… • States of matter • Phase changes • Physical/chemical properties and changes • Density and specific heat calculations • What we have yet to discuss… • Classification of matter • How to separate matter physically • Test next Tuesday, September 19th

2. Essential Questions How is matter classified? How can mixtures be separated?

3. Classification of Matter • Pure Substance– materials that always have the same (definite) composition B. Mixture – 2 or more different materials physically combined

4. Pure Substances 1. Element – simplest forms of matter made up of one type of atom Ex: carbon, sodium, helium 2. Compound – substance that is made from the atoms of two or more elements that are chemically bonded Ex: NaCl – sodium chloride sugar (sucrose) – C12H22O11

5. Mixtures 1. Homogeneous – uniform in composition & properties throughout Ex) salt water, air, alloys

6. Homogeneous Mixture Example Solution– homogeneous mixture consisting of a solute & a solvent i . solute – dissolved material ii. solvent – material doing the dissolving

7. Mixtures Cont. • Heterogeneous – not uniform in composition & properties throughout • Ex: sand, chocolate chip cookie dough a. Suspension – particles are dispersed throughout a liquid, but eventually settle out (muddy water)

8. Review How would you classify matter that you cannot separate physically, but you can chemically?

9. Review How would you classify matter that you can separate physically, and is not uniform throughout?

10. Review How is a colloid different from a solution? How is a colloid different from a suspension?

11. Review Describe the Tyndall Effect.

12. b. Colloid – tiny particles are dispersed throughout another substance, but will not settle out (jello) • Aerosols –solid or liquid particles in a gas Ex. Spray paint, fog, smoke • Foams – a gas in a liquid Ex. whipped cream, marshmallow • Emulsion – a liquid in a liquid Ex. mayonnaise. cheese • Sols – solids in liquids or solids in solids Ex. jellies, Jello!

13. Emulsion https://www.google.com/#q=breaking+bad+emulsion

14. 1. Separation of a Mixture *Mixtures can occur in any state or combination of states and can be separated physically

15. Lab # 3 Writeup Intro: a procedure of what you did in paragraph form. Include the name of the technique you used Data: Any data you recorded in list format Data Analysis: Calculation in lab. Be sure to label Conclusion: answer the questions in the lab as thorough as you can.

16. Filtration • Separates an insoluble solid from a liquid • Solid is collected on filter paper • Filtrate (remaining liquid) is collected in a beaker • LAB HINTS: • Always measure the mass of your filter paper before filtering

17. Evaporation • Used when 2 substances have different boiling points • Only 1 of the substances remains • LAB HINTS: • Measure the mass of • the empty evaporating dish • Don’t heat on high the entire time

18. Distillation Separation of two liquids with different boiling points

19. Extraction • LAB HINTS: • You can also use a pipet if you don’t have a separatory funnel • Separation based on differences in solubility in at least two different solvents (liquids)

20. Centrifuge • Used to collect precipitate formed from two solutions • 1stcentrifuge the mixture • Uses centripetal force to push solid to bottom • 2nddecant (pour off) the remaining liquid

21. Magnetism & Floatation Magnetism-separates one magnetic substance from a non-magnetic substance LAB HINT: Wrap magnet in plastic wrap Floatation-uses the concept of different densities to separate a mixture

22. How would you separate the following mixtures? When two liquids combine, a precipitate (solid) is formed. How would you separate the precipitate from the remaining solution?

23. How would you separate the following liquids? You have two liquids with very different boiling points. What technique would you use to separate them if you want to end up with both liquids? If you only need to keep one of the liquids?

24. Separation of a mixture How would you separate a mixture containing corn oil, salt, and water?

25. Lab You have a mixture of salt, sand, iron, and styrofoam. Describe a procedure you could do to end up with all four components. (This will be multiple steps)

26. Lab • Get a weigh boat, put your names on it, find mass • Get sample from Mr. Keith, find mass of mixture • Use the following techniques to separate mixtures: Note: Be sure to measure and label EVERYTHING!!!!!!

27. Essential Question How do matter and energy relate to chemistry?

28. Conservation of mass Think: looking at the name, what is your own definition of the conservation of mass? Think about the conservation of energy

29. Conservation of Mass • In a closed system, the mass of the reactants is equal to the mass of the products. • CaC2 + H2O  Ca(OH)2 + C2H2 • Example: Calcium carbide and water react to form calcium hydroxide and acetylene. If 8.0 g of calcium carbide react with 10.0g of water to form 16.0 g of calcium hydroxide, what mass of acetylene was produced?

30. Endothermic vs. Exothermic What is the difference?

31. Endothermic vs. Exothermic Ammonium nitrate + barium hydroxide Draw an energy diagram for this reaction.