1. Matter…matters

2. Density Density is a property of matter One way to identify a substance is by its density. Gold or Fools Gold? (pyrite)

3. How to find DENSITY Step 1: Measure the mass Step 2: Measure or calculate the volume

4. Finding Volume Shape Formula Rectangular prismv=length * width * height Triangular prismv=1/2 (length * width * height) Cylinderv = pi r 2 h

5. Volume of Irregular Shapes Step 1: Read the graduated cylinder. http://www.morrisonlabs.com/meniscus.htm Step 2: Place the object in the cylinder Step 3: Read the graduated cylinder. Step 4: Calculate the difference of the water displacement to find the volume of the irregular shape.

6. Step 3 Density = mass divided by volume

7. Calculate the density for each item. D = M / V Mass: 15 g Volume: 20 mL Mass: 1000 g Volume: 50 mL Mass: 225 g Volume: 100 mL Mass: 10 g Volume: 200 mL www.middleschoolscience.comwww.middleschoolscience.com 2008 Density =.75Density = 20Density = 2.25 Density = 0.05

8. The king wants to pick out a new crown but only wants one made of 100% pure gold, not gold plated or mixed with other metals. Can you help him find his new gold crown? The volume of each crown is 60 cm 3 Densities of Metals Lead – 11.34 g/cm 3 Gold -19.3 g/cm 3 Silver -10.5 g/cm 3 Platinum - 21.4 g/cm 3 Copper - 8.9g/cm 3 D = M / V A = 680.4 gB = 534 g C = 1,158 gD = 1,284 g L. LaRosa http://www.middleschoolscience.com for T. Trimpe 2008 http://sciencespot.net/

9. D = M / V A = 680.4 g B = 534 g C = 1,158 g D = 1,284 g D = 680.4 / 60 D=11.34 g/cm 3 D = 534 / 60 D=8.9 g/cm 3 D = 1158 / 60 D=19.3 g/cm 3 D = 1284 / 60 D=21.4 g/cm 3 The volume of each crown is 60 cm3

10. The king wants to pick out a new crown but only wants one made of 100% pure gold, not gold plated or mixed with other metals. Can you help him find his new gold crown? The volume of each crown is 60 cm 3 Densities of Metals Lead – 11.34 g/cm 3 Gold -19.3 g/cm 3 Silver -10.5 g/cm 3 Platinum - 21.4 g/cm 3 Copper - 8.9g/cm 3 D = M / V A = 680.4 gB = 534 g C = 1,158 gD = 1,284 g