1. April 27, 2011  Attendance  Coke vs. Diet Coke  Correct 12.1A Density Homework (white)  Discuss Lab 12A  Use water displacement tanks to find volume  Learning Targets:  Find volume of an object using water displacement.  Apply the formula: D = M/V  Examine variations in densities of matter in different states.

2. Table of Contents DateTopicPage 4/7Matter Web Quest47 4/8Particle Theory of Matter48 4/12The Atom/MCA Testing49 4/14States of Matter50 4/19Physical Properties of Matter51 4/20Oobleck!52 4/25Density53 4/27Density (continued)54

3. Density (cont)4/27/11 54 Summary:

4. Coke vs. Diet Coke How do you find the density of an object? What is the formula for density? How can we find out the volume of the bottles? How do we find the mass of the bottles? Density = Mass Volume What might cause the density of the sodas to be so different ? Sink or Float?

5. 12.1 Density 1. A solid rubber stopper has a mass of 33.0 grams and a volume of 30.0 cm 3. What is the density of the rubber? Density = Mass Volume Density = 33.0 30.0 = 1.1 gr/cm 3

6. 2. A chunk of paraffin (wax) has a mass of 50.4 grams and a volume of 57.9 cm 3. What is the density of paraffin? Density = Mass Volume Density = 50.4 57.9 = 0.87 gr/cm 3

7. 3. A marble statue has a mass of 6,200 grams and a volume of 2,296 cm3. What is the density of marble? Density = Mass Volume Density = 6,200 2,296 = 2.7 gr/cm 3

8. 4a-b. 4. Full Box = 120.8 kg Empty = 0.755 kg 120.8 kg - 0.755 kg = 120 kg of plastic 120 kg 0.125 m 3 = 960 kg/m 3 Type of Plastic = HDPE

9. b. HDPE, LDPE, PP, PS

10. 12A Density Lab Discussion Check your answers. How close are you? Make changes to your table as needed.

11. Compare the answer in the “mass” column with your answer. Make changes as needed. You will also have to recalculate each density.

12. Compare the density of each material against water = 1 g/cm 3. If the density is greater than water the material should sink. If the density is less than water the material should float.

13. Water Displacement Archimedes was born in Greece in 287 B.C.

15. 12A Density Lab - Challenge How do you use a displacement tank to measure the volume of a cube? Find the volume of each cube by using the water displacement technique. Compare your results with those you obtained using the mathematical formula (see Table 2). How close are your answers? Answer the questions for Challenge 5d on the last page of your lab packet.

16. Wrap Up Summary: You have found volume of objects using two different methods (formula and water displacement). Describe each method. Which technique do you prefer? Why? Homework: None Today! Flipper: 12A lab goes back to spread #53