Warm-up 1/30/12

1. Warm-up 1/30/12 What is chemistry? Give an example (or examples) of chemistry in your life.

2. Today • Starting our chemistry unit! • What’s happening to those cans? Observations and hypothesis • Introduction to Tools that Chemists Use

3. Learning Targets • Define volume • Become familiar with using and reading tools for measuring mass and volume • Examine and describe the relationship between mass and volume of an object

5. Warm-up 1/31/12 If you fill up a bathtub to the top with water, why does water spill over the edge when you get in?

6. Today • Finish Pre-lab • Learn how to read a meniscus • Measuring Volume Lab

7. Learning Targets • Define volume • Become familiar with using and reading tools for measuring mass and volume • Examine and describe the relationship between mass and volume of an object

8. Measuring Volume Lab: Learning Targets What will we be learning and doing in this lab? • Define volume • Become familiar with using and reading tools for measuring mass and volume • Examine and describe the relationship between mass and volume of an object

9. Meniscus: the curve at the top of a liquid when it is in a graduated cylinder

10. How to read a graduated cylinder Read the meniscus at EYE-LEVEL Look at the BOTTOM of the curve

11. Practice!

12. How to measure volume using WATER DISPLACEMENT 4.8mL 5.6mL A. Measure the volume of water in your tool BEFORE you put the object in. B. Measure the volume of water AFTER you put the object in. Volume = B-A Volume = 5.6 – 4.8 = 0.8mL

13. Question: • Which tools are best for measuring the mass and volume of small objects? • Which objects have the greatest volume (displace the most water) ?

14. Hypothesis • In your journal, write your predictions: • Which tool will work the best to measure volume (water displacement)? • Which object will move the most water? • Which object will sink or float?

15. What is the volume of liquid in the two containers below? B A

16. Discuss these questions with your group, and write down your best and most complete answer. • Why is it important to be precise in our measurements? • Why is it important to know which tools can do what? • Did you see a relationship between mass and volume? Between mass, volume, and floating?

17. Exit Slip • What is the volume of liquid in this 10mL graduated cylinder?

18. Warm-up 2/3/12 • When you blow up a balloon, does its volume change? Does its mass change? Explain.

19. Today • Make your science folder; go over syllabus • Go over graduated cylinder worksheet (homework) • Write conclusion for Measuring Volume Lab • Mass and Change Lab • Exit Task: Daily Reflection Sheet

20. Learning Targets • Define mass and distinguish between mass and weight. • Explain the difference between mass and volume. • Compare an “open system” and a “closed system”. • Explain what conservation of mass is.

21. In your groups: • Draw a TABLE of raw data • Draw a GRAPH of raw data • Write a conclusion statement. What does this lab tell you about mass? When we change the form of an object, its mass ______________________________________. (increases, decreases, or stays the same?)

22. Warm-up 2/6/12: Complete the sentences according to what you learned in the Mass and Change Lab If we take a marshmallow and smash it into a tiny ball, its mass will ________. (increase, decrease, or stay the same) This is because __________________ _______________________________.

23. Today • Wrap up Mass and Change Lab: What did we learn? • Demonstration: What happens when we mix sodium carbonate and calcium nitrate? • Video: What is Mass? • Complete Mass and Volume Table • Exit Task: Daily Reflection Sheet

24. Learning Targets • Explain the difference between mass and volume. • When objects change form, what happens to their mass?

25. Mass and Change Lab: Summary

26. Conclusion: When an object changes form, the mass stays the same. In a closed system, MASS IS ALWAYS CONSERVED.

27. Demonstration • Describe what you saw happen when the two substances were mixed together. • Predict what happened to the total mass. • Does this demonstration tell us the same thing as the Mass and Change Lab?

28. What is mass? • Eureka! Mass Video

30. Exit Ticket Put the following in order from MOST massive to LEAST massive: Wood block, styrofoam block, lead block (they are all 10cm³)

31. Warm-up 2/7/12 When we dissolved the Alka-Seltzer, the mass of the system did not change. Where did the matter go, or how did it change?

32. Today • How to draw particle diagrams • Particle diagram practice • Finish worksheet for homework

33. Learning Targets • Explain what happens to mass when an object changes form. • Use particle diagrams to show how substances change at a particle level.

34. What is a particle diagram? • A model that shows substances at an atomic level • Scientists use particle diagrams to help them visualize how particles interact. What are particle diagrams really showing? • Zoom in to Aluminum

35. Particle diagrams … Show particles as circles or other shapes Show more MASS by showing more PARTICLES

36. Particle diagrams … Distinguish between different types of particles by using different shapes

37. Warm-up 2/9/12 Make a list of things that you think are DENSE and NOT DENSE.

38. Today • Density Lab • Part 1: Mass, volume, and density of your metal • Part 2: Whiteboard summaries • Part 3: Comparing group data • Exit Task: Daily Reflection Sheet AND Exit Ticket

39. Learning Targets • Explain the relationship between mass, volume, and density. • Identify an object based on its density.

40. Density Lab Part 1 • Visit Station 1 and Station 2 • Collect data and record in your chart • After data collection, do your calculations

41. Density Lab Part 2 • In your groups, use your data to make 3 graphs: • Number of metal pieces vs. mass • Number of metal pieces vs. volume • Number of metal pieces vs. density Put your graphs on a whiteboard and be ready to share with the class.

42. Density Lab Part 3 • Get together with a group that has the same letter color as you. • Compare your metal pieces. What is the same? What is different? • Compare your graphs. What is the same? What is different? • Write a conclusion: What does this lab tell us about density, mass, and volume?

43. Warm-up 2/10/12 OMG. These weights are sooo dense. What does “dense” mean in these two situations? OMG. That guy is soooo dense.

44. Today • Figure out your mystery metal • Comparing “density” and “weight”: what is the difference? • Worksheet 2 • Daily Reflection: fill out today’s entry and the BACK; turn in at end of period

45. Learning Targets • Define density. • Explain the relationship between mass, volume, and density. • Identify an object based on its density.

46. Figure out your mystery metal! Look at your density data from the Density Lab. According to your data, which type of metal did you have?

47. What is density? Density = Mass ÷ Volume • Density is a measure of how tightly packed particles are in a substance • MORE dense = MORE stuff in the same amount of space

48. Showing density in a particle diagram • When particles are closer together, they are showing that a substance is MORE DENSE. Each particle is a tiny, tiny bit of mass. • Which particle diagram shows a high density?

49. Density vs weight • Which one has more mass: the stopper or the cork? • Which one is more dense, the stopper or the cork? • Mass (weight) = how much stuff is in a substance • Density = how packed the substance is

50. Warm-up 2/13/12 You want to identify a strange piece of metal. How do you identify it? (Hint: use what we’ve learned about mass, volume, and density.)