Density

1
Density

• EQ Why do some objects float and other objects
  sink?

2
What is density?

• .

• Density is a comparison of how much matter there
  is in a certain amount of space.
• Each substance has a specific density.
• Density can be used to identify a substance

Substance Density (at 20C
Wood 0.70 g/cm3
Corn oil 0.92 g/cm3
Water 1.00 g/cm3
Rubber 1.34 g/cm3
Copper 8.80 g/cm3
3
Which one is more dense?

• Demonstration People in a square
• How about this Which square is more dense?

4
Which one is more dense?

• Now which one is more dense?

5
What is density?

•  

ALWAYS REMEMBER UNITS!
6
Lets try a density problem together

• Frank has a paper clip. It has a mass of 9 g and
  a volume of 3 cm3. What is its density?
• 9 g 3 cm3 3 g/cm3
• Frank also has an eraser. It has a mass of 3 g,
  and a volume of 1 cm3. What is its density?
• 3 g 1 cm3 3 g/cm3

7
Work on these problems with your neighbor.

• Jack has a rock. The rock has a mass of 6 g and a
  volume of 3 cm3. What is the density of the rock?
• Jill has a gel pen. The gel pen has a mass of 8 g
  and a volume of 2 cm3. What is the density of the
  rock?

8
Now, try these on your own.

• Alicia has a watch. It has a mass of 4 g and a
  volume of 2 cm3. What is the density of the
  watch?
• Mia has a wallet. It has a mass of 15 g and a
  volume of 5 cm3. What is the density of the
  wallet?

9
What if you already know density?

• Use the density triangle, or DMV, to solve for
  the missing part.
• D MV
• V MD
• M DV

10
Liquid Layers Try with your neighbor

• Which liquid has the highest density?
• Which liquid has the lowest density?
• Which liquid has the middle density?

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Liquid Layers Try on your own!

• Imagine that the liquids on the right have the
  following densities
• 15 g/ml 10 g/ml
• 3 g/ml 9 g/ml
• 7 g/ml 12 g/ml
• Match the colors to the correct densities.

3 g/ml
7 g/ml
9 g/ml
10 g/ml
12 g/ml
15 g/ml
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Super Scientist Question of the Day

• Jake has a book, a ruler, and a balance.
• How can Jake find the density of the book with
  the tools he has?