1. 30Sep14 WarmUp What are the three phases of matter? Density is a ratio that compares the _______ of an object to its ____________ Give some examples of “physical characteristics”

2. Matter Matter is anything that has mass and takes up space

3. Phases of Matter Which has its own definite shape? Which flows to fill the shape of the container? Which flows to conform to the shape of the container but doesn’t fill it?

4. Phases of Matter What is the difference between a gas and a vapor? Vapor refers to the gaseous state of something that is either a solid or liquid at room temperature Gas refers to a substance that is found in gaseous form at room temperature

5. Properties of Matter Physical property – a characteristic of matter that can be observed or measured without changing the sample’s composition (what it’s made of) Examples: color, physical state, melting point, boiling point, density at a given temperature, odor

6. Properties of Matter Two types of physical properties  Extensive properties Are dependent on the amount of substance present  Intensive properties Independent of the amount of substance present

7. Properties of Matter Chemical property – the ability or inability of a substance to combine with or change into another substance Examples: Iron forming rust, copper turning into copper carbonate (green) when in moist air

8. Properties of Matter Physical change – a change that alters a substance without changing it’s composition Phase change – transition of matter from one state to another gas  liquid  solid Chemical change – a process that involves one or more substances changing into a new substance Formation of rust from iron when exposed to oxygen

9. Conservation of Mass The Law of Conservation of Mass states that mass is neither created nor destroyed during a chemical reaction mass reactants = mass products

10. Conservation of Mass Examples In a complete reaction of 22 g of sodium (Na) with 32 g of chlorine (Cl), what mass of sodium chloride is formed?

11. Conservation of Mass Examples In a complete reaction of 2 g of hydrogen (H) and 4.5 g of oxygen (O), what mass of hydroxide is formed?

12. Conservation of Mass Examples A 12g sample of helium (He) is reacted with a sample of boron (B) to form 22g of HeB. What was the mass of the boron?

13. Substance Pure Substance – has a uniform and unchanging composition Examples - tin, sulfur, diamond, water, pure sugar (sucrose), table salt (sodium chloride) and baking soda (sodium bicarbonate)

14. Mixtures Mixture – a combination of two or more substances in which each pure substance in it retains its individual properties

15. Mixtures Heterogenous mixture  does not blend smoothly throughout  individual substances remain distinct  Not uniform Examples salad dressing, orange juice

16. Mixtures Homogenous Mixture  Constant composition throughout  Always has a single phase Examples Tea, lemonade, salt water

17. Mixtures Homogenous mixtures are also called solutions.

18. Mixtures Types of Solution Systems SystemExample gas-gas air in a SCUBA tank is a mixture of N, O, Ar gas-liquidO and CO2 is dissolved in seawater liquid-gas Moist air exhaled by the diver contains water droplets liquid-liquid When it is raining, fresh water mixes with seawater solid-liquidsolid salts are dissolved in seawater solid-solidair tank is a mixture of two metals

19. Separating Mixtures Filtration – uses a porous barrier to separate a solid from a liquid Distillation – based on differences in the boiling points of the substances

20. Separation of Mixtures Distillation video

21. Separating Mixtures Crystallization – results in the formation of pure solid particles of a substance from a solution

22. Separating Mixtures Sublimation – when a solid changes to vapor without going through the liquid phase

23. Separating Mixtures Chromatography – separates the components of a mixture by drawing the mixture (liquid or gas) (mobile phase) across a fixed substrate (stationary phase)

24. PhET demo Extensive or Intensive? Demonstration: Wood Floating

25. Summary Questions Heterogenous or homogenous? Tap Water Air Raisin muffin

26. Summary Physical or Chemical Property? Freezing point pH Flammability Viscosity

27. Summary Extensive or Intensive? Odor Length Conductivity Density Weight

28. Summary Physical or Chemical Change? Burning Digesting food Melting an ice cube Breaking a beaker

29. Summary Examples of substances Is CO2 (g) a pure substance? Why or why not? Is tea a pure substance or a mixture?

30. Summary C 6 H 12 O 6 + O 2  H 2 O + CO 2 When burning 180 g of glucose in the presence of 192 g of oxygen, water and carbon dioxide is produced. If 108 g of water is produced, how many grams of carbon dioxide are produced?

31. Summary Questions How would you separate them? Two colorless liquids A non-dissolving solid mixed with a liquid Red & blue marbles of same size and mass