2. Wacky Soda Demo WHY?

3. Mystery Liquids #1 Did you discover more than one combination that would work? What do you think the liquids are?

4. Mystery Liquids # 2 What do you think keep the liquids separate? Which layer was just water? Give an example of two gases with different densities. How do you know they have different densities?

6. In your science notebook…. Today’s date: 3/21/2012 Title: Lava Lamp & Density Draw a lava lamp and describe how you think the lamp works inside. (HINT: think about our density discussions)

7. SubstanceMass (grams) Volume (cm 3 ) Density (g/cm 3 ) Bar A110100 Bar B95100 Water100g100 cm 3 1.0 g/cm 3 Problem: Two different bars of soap are being investigated by a group of students. The students measured the mass and volume of each bar and recorded it below. Calculate the density of each bar of soap. Show your work. Homework Review 1.1 g/cm 3 Density =M/V Bar A: 110g/100cm 3 = 1.1 g/cm 3 Bar B: 95g/100cm 3 = 0.95 g/cm 3 0.95 g/cm 3 A B

8. Step 1 Read the problem. Step 2 Write the formula. “Copy” Step 3 Replace the words with the numbers and units. “Substitute” Step 4 Divide mass by the volume “Evaluate” Step 5 Write the answer and include units. If 96.5 grams (g) of gold has a volume of 5 cubic centimeters (cm 3 ), than what is the density of gold? Density = Mass/Volume Density = 96.5 grams/5 cm 3 Type in 96.5, hit ÷ Type in 5, hit = 19.3 Density = 19.3 g/cm3 Finding Density using Math

9. SubstanceMassVolumeFormula/My MathDensity Air.026 g20 cm 3 Gasoline 21.0 g 30 cm 3 Wood (oak) 34.0 g40 cm 3 Water (ice) 36.8 g40 cm 3 Water (liquid) 1.0 g 1 cm 3 Aluminum 96.5 g35 cm 3 Steel273.0 g35 cm 3 Silver367.5 g35 cm 3 Gold675.5 g35 cm 3 Platinum752.5 g35 cm 3

10. WeightVolumeFormula/My MathDensitySubstance 1.35 g15,000 cm 3 G 2.67 g15,000 cm 3 G 19.5 g15,000 cm 3 G 3200. g 2000 cm 3 L 2000. g 2000 cm 3 L 3600. g 2000 cm 3 L 1800. g 2000 cm 3 S 1840. g 2000 cm 3 S 5600. g 3500 cm 3 S

11. 1. Density is a property of all matter Matter is any object that takes up space and has mass 2. Density measures how tightly packed the mass is in an object

12. 3. Density measures how much mass is squeezed into a space.

13. 4. A dense object feels “heavy” for its size. A one –pound rock and a one-pound pillow have the same mass, but the rock is a lot denser; the rock takes up less space.

14. 5. Densities of fluids, liquids and gases, can be compared usually by which fluid floats and which fluid sinks.

15. 6. Densities can be measured by using MATH The formula for density is d = density m = mass (grams) v = volume (ml or cm 3 )

16. Density practice MaterialMass Volume Formula Density Wood (oak) 34.0 g 40 cm 3 Ironwood51.2 g 40 cm 3 Water40 g 40 cm 3 0.85g/cm 3 1.28 g/cm 3

17. Melting Ice Cube Lab What happened to the ice when you first placed the cubes in the jars? Describe the pattern the food color made in each of the jars… Why do you think there was a difference in the pattern?

18.  Why did the food coloring ‘drop’ to the bottom of the fresh water jar?  Why did the food coloring stay on top of the salt water jar?  Why did the ice cubes stop melting in the salt water jar?  What will cause the salt water jar to eventually mix?