WALT:

• Gain background knowledge on density to lay the foundation for future learning

• Define density various ways

• Compare the densities of 2 objects

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Density: Warm Up Questions

• What is the meaning of “population density”?

• Which state do you think has the greatest population density?

• Which state do you think has the lowest population density?

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Population Density: the number of people living in a particular area (people per square mile)

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Greatest Population Density: New Jersey! Yay!Estimate the following on your sheet:

• # of people:

• Area:• Population Density:

8,707,7398,721 mi2

~998 people/mi2

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Lowest Population Density: Wyoming!Estimate the following on your sheet:

• # of people:

• Area:• Population Density:

530,000

97,818mi2

5.4 people/mi2

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Mass: Amount of matter in a substance; measured in grams (g)

with an electronic balance

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Volume: Measure of the amount of spaceSolid units: cm3 Liquid/Gas units: mL

Irregular Objects

-Water Displacement method

Regular Objects

- Measure and calculate8

1 cm3 = 1 mL

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Density: Definitions

There are 6 definitions of density. Each of these definitions is explained on the next 6 slides, and there is a spot for you to copy

each definition on your Powerpoint guide.

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Density Definition #1

•Density = mass

volume

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Density Definition #2

• Density = unit of mass

unit of volume

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Density Definition #3

• Density = known mass

known volume

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Density Definition #4• Compactness: objects that are more dense are more

compact

Both cubes have the same volume Both cubes have the same volume

This cube has more matter in it

This cube has more matter in it

Therefore, this cube is more dense (or more

compact)

Therefore, this cube is more dense (or more

compact)14

Density Definition #5

• Density = mass

volume

= g

cm3

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Definition #6: mass of 1 cm3 of a substance

1 cm3

1 cm3

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Comparing Densities #11 cm3 of concrete vs. 1 cm3 of air?

1a. Which has more mass?

1b. Which has a greater volume?

1c. Which has a greater density?

Explain your reasoning for your answers.

Concrete

They have the same volume

Concrete

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2a. Which has a greater mass?2b. Which has a greater volume?2c. Which has a greater density?

Pb

Wood ShavingsLead Block

Lead block

Wood Shavings

Lead block

Comparing Densities #2

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Assume each box has a volume 1 cm3

Assume each red ball is equal to 1 g of matter Calculate the density of each object—show your calculations:

Substance A Substance B

Comparing Densities #3

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One of the substances with the highest density?

Gold = 19.3g/cm3

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Most dense known

substance

Osmium—22.57g/cm3

Hydrogen – 0.000089g/mL

Least dense known substance

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Floating and SinkingDensity of Air = 0.0013 g/cm3

Density of Helium = 0.00018 g/cm3

Density of Tank = ???

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Density of Pure Water: 1.0 g/cm3

Density of a person: less than that

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Density Output

• On page 42 of your interactive notebook, draw a picture that represents an object of high density AND an object of low density. Represent the matter in each object with dots. Remember to label each object.

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