1. Today’s Do Now 8/19/14 A chemist classifies set of 3 laboratory observations in his lab notebook, but he forgot to label the observations as physical or chemical changes. Which of the data set(s) include two chemical changes and one physical change? Write a sentence defending your answer choice(s).

2. Data Set A Observation 1Powder is added to an unknown liquid in a beaker. The solution begins to bubble and smoke rises. Observation 2A ball of wax is melted into a liquid mixture. Observation 3Liquid wax is poured into a mold and cools to take the shape of a beaker. Data Set B Observation 1To replicate an ocean environment for a new specimen, salt is mixed into the water in the fish tank. Observation 2Four droplets of a buffer are added to the fish tank. The recorded pH after the droplets are added is higher than the original pH. Observation 3The water level in the tank has dropped when measured the following morning. There appear to be no leaks or mechanical issues with the tank. Data Set C Observation 1A lab rodent got its foot caught in the cage. The ulna and radius bones appear to be broken. Observation 2The side of the wire cage has a layer of rust. Observation 3The lab rodent eats a pellet of food and the food is reduced to waste.

4. By the end of the class period today I will be able to… Differentiate between pure substances and mixtures

5. Today’s Game Plan Do Now10 minutes Is Ink a Pure Substance or Mixture? 3 minutes Pure Substances and Mixtures 12 minutes Raise ‘em up!!8 minutes Go with the Flow…Chart and How to Separate Mixtures 20 minutes Independent Practice20 minutes Closing/Exit Ticket15 minutes

6. Make a Hypothesis…Is ink a pure substance or mixture? Ask yourself, based on what you already know: What is a pure substance? What is a mixture? What do you think the difference between the two is? How do you think we can use science to figure out whether ink is a pure substance or mixture? Place your piece of filter paper in the cup of water. Be sure that the water does not directly touch the ink!

7. Today’s Game Plan Do Now10 minutes Is Ink a Pure Substance or Mixture? 3 minutes Pure Substances and Mixtures 12 minutes Raise ‘em up!!8 minutes Go with the Flow…Chart and How to Separate Mixtures 20 minutes Independent Practice20 minutes Closing/Exit Ticket15 minutes

8. Pure Substances Composition is the same throughout and does not vary from sample to sample. CANNOT be broken down by physical changes Can be an element or compound.

9. Element Definition: substances in their simplest forms Cannot be broken down by a physical or chemical change Found on the periodic table Made up of one type of atom

10. Examples of Elements: Hydrogen Carbon Lithium Gold What are two other examples of elements not listed above? What do all elements have in common?

11. Compound Definition: substance formed by the chemical combination of two or more elements can be broken into simpler substances by a chemical change + = Compound

12. A compound is always composed of the same elements in the same proportions. In other words, Carbon Dioxide (CO 2 ) is always composed of 1 atom of C and 2 atoms of O. If there are different amounts of carbon or oxygen, it is no longer carbon dioxide. Law of Definite Proportions

13. More Examples of Compounds

14. Mixture Definition: two or more pure substances (elements or compounds) that are mixed together but NOT joined chemically NOT a pure substance Examples: The air we breath, gasoline for cars, the sidewalk on which we walk

15. Homogeneous Mixtures Uniform in composition and appearance Same proportion of components throughout Consists of two or more substances in the same phase Also called solutions Uniform in composition and appearance Same proportion of components throughout Consists of two or more substances in the same phase Also called solutions

16. Heterogeneous Mixtures variable appearance and composition

17. Today’s Game Plan Do Now10 minutes Is Ink a Pure Substance or Mixture? 3 minutes Pure Substances and Mixtures 12 minutes Raise ‘em up!!8 minutes Go with the Flow…Chart and How to Separate Mixtures 20 minutes Independent Practice20 minutes Closing/Exit Ticket15 minutes

18. Raise ‘em Up! Look at the following example and with your partner determine if it is a heterogeneous mixture, homogeneous mixture, element, or compound

19. Chicken Noodle Soup

20. Pure Water

21. Tap Water

22. Pure Gold

23. Coca-Cola

24. Helium

25. Today’s Game Plan Do Now10 minutes Is Ink a Pure Substance or Mixture? 3 minutes Pure Substances and Mixtures 12 minutes Raise ‘em up!!8 minutes Go with the Flow…Chart and How to Separate Mixtures 20 minutes Independent Practice20 minutes Closing/Exit Ticket15 minutes

27. Kool Aid has mass and takes up space

28. Can be separated by allowing water to evaporate

29. Same composition throughout

30. Your turn! With your groups, you will have 3 minutes to choose an example and use the flow chart to classify it. Beware – I will be choosing groups at the end of class to present their examples!

31. So…how do we know if a mixture can be “broken down physically”? What are some examples of breaking a substance down physically?

32. Separation of Mixtures Decantation Evaporation Filtration Chromatography Magnetism

33. Chromatography Demo Chromatography = a way to separate a mixture based on polarity mobile phase – substance that is moving/facilitating the separation stationary phase – substance that is NOT moving, fluid moves through it The various parts of the mixture travel at different speeds, causing them to separate!

34. Polarity and Chromatography Polarity – the separation of charge in a molecule Causes attraction between molecules Different molecules exert different forces of attraction on each other resulting in different solubilities

35. CHROMATOGRAPHY DIFFERENT POLARITY DIFFERENT SOLUBILITY DIFFERENT DISTANCES TRAVELED = SEPARATION

36. Revisiting your hypothesis… Is ink a pure substance or mixture? Defend your answer using DATA from the demonstration. Remember – data can be quantitative or qualitative Is ink a homogeneous or heterogeneous mixture? How do you know?

37. Today’s Game Plan Do Now10 minutes Is Ink a Pure Substance or Mixture? 3 minutes Pure Substances and Mixtures 12 minutes Raise ‘em up!!8 minutes Go with the Flow…Chart and How to Separate Mixtures 20 minutes Independent Practice20 minutes Closing/Exit Ticket15 minutes

38. Today’s Game Plan Do Now10 minutes Is Ink a Pure Substance or Mixture? 3 minutes Pure Substances and Mixtures 12 minutes Raise ‘em up!!8 minutes Go with the Flow…Chart and How to Separate Mixtures 20 minutes Independent Practice20 minutes Closing/Exit Ticket15 minutes

39. Closing “Volunteers” to share their example with the class Why is it important for us to understand how to classify matter? Our first formal lab report!

40. Lab Procedure You are responsible for coming up with a procedure as a lab group. I must sign off on this procedure before you can begin your lab.

41. Homework Complete Pure Substances and Mixtures Worksheet (due next class) Read the lab packet before next class. You will have some class time with your group to write your procedure (prelab) but it must be completed and approved (by the teacher) before you can begin the lab Begin working on Unit 1 Review Packet

42. Exit Ticket 1. Compare and contrast the terms element and compound. Label these substance as an element or a compound. 2. Distilled Water 3. Magnesium 4. Iron 5. Oxygen 6. A student wants to analyze a substance as either a pure substance or a mixture. Describe in a complete sentence the way this student can distinguish between pure substances and mixtures. 7. Two grams of potassium chloride are completely dissolved in a sample of water in a beaker. This solution is classified as a. An element b. A compound c. A homogeneous mixture d. A heterogeneous mixture 8. In the lab, Salma had an unknown liquid that had the same composition throughout the whole sample. She heated the liquid over a Bunsen burner and collected the gas that was given off. She analyzed that sample of gas and found it had the same chemical composition as the original liquid. What type of substance was she working with? How do you know?