1. Bell Ringer
Pumice is a volcanic rock that floats on top of water. All other rocks will sink in water. With your group, why do you believe Pumice rock floats?
Answer on White board.

2. Measuring Density (page 8)
*Density - How much mass is in a given amount of space (volume)
**The ratio of matter to volume in an object or substance

3. *Units - g/cm³ (grams per centimeters cubed, or grams per cubic centimeter)

4. 4. Measuring Density *How to calculate:
1 – Measure the mass of the object
2 – Measure the volume of the object
3 – Calculate the density
Density (D) = Mass (M) ÷ Volume (V)
D = M ÷ V

5. 4. Measuring Density 1 – Measure the mass of the object
Object Object 2
100 g g

6. 4. Measuring Density 2 – Measure the volume of the object
Object Object 2
10 cm x 5 cm x 4 cm cm x 5 cm x 4 cm
= 200 cm³ = 200 cm³

7. 4. Measuring Density 3 – Calculate the density (D = M ÷ V)
Object Object 2
D = 100 g ÷ 200 cm³ D = 600 g ÷ 200 cm³
= 0.5 g/cm³ = 3 g/cm³

8. Measuring Density
*How much mass is in a given volume

9. Density Mass = 4000g Volume = 5000 mL Density = 4000g ÷ 5000 cm³

10. Density Mass = 10,000g Volume = 5000 mL Density = 10,000g / 5000 cm³

11. Density
0.8 g/cm³ g/cm³

13. What causes an object to float on water instead of sinking?

14. Water has a density of 1.0 g/cm³
Objects with a lower density than water will float, with a greater density will sink

15. Density
0.8 g/cm³ g/cm³

16. Here We Go

17. Closing
Quick Write – You have a foam ball and a bowling ball that are identical in size. Explain, in detail, why the foam ball would float in a tank of water, but the bowling ball would sink *Do this below your notes