What is Density?

1
What is Density?

• The ratio between the mass of an object and the
  volume of the same object
• In other words, it tells you how much matter an
  object has within a given amount of space
  (volume)
• Each element has a specified density. For
  example platinum 21.4g/ml and silver
  10.5g/cm3
• 1 ml 1 cm3

2
More on Density

• Density is a physical property of matter. It is
  a characteristic that applies to a specific
  substance, such as odor, color, and texture.
• The density of a pure substance never changes,
  except for gases.
• Physical properties that do not depend on how
  much you have of the substance are called
  intensive properties, such as density
• A physical property that depend on the amount of
  substance is called an extensive property.

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Definitions

• Mass how much matter a substance has
• Volume how much space the substance takes up
• Density how packed the matter is

4
Determining Density

• Take the mass of the object and divide by the
  volume Mass
• volume
• Example
• An object with a mass of 20 grams and a volume of
  10 milliliters has a density of 2g/ml.
• 20g 20g 10ml 2g/ml
• 10ml
• The answer 2g/ml is read 2 grams per one
  milliliter.

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D. Density

• An object has a volume of 825 cm3 and a density
  of 13.6 g/cm3. Find its mass.

GIVEN V 825 cm3 D 13.6 g/cm3 M ?
WORK
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D. Density

• A liquid has a density of 0.87 g/mL. What volume
  is occupied by 25 g of the liquid?

GIVEN D 0.87 g/mL V ? M 25 g
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Calculate

• Mass 4.53 kg and volume 225 cm3
• Mass 122.4 g and volume5.5 ml
• Find the mass if the density is 2.14g/cm3 and the
  volume is 8cm3

8cm3 2.14g
1 cm3