DENSITY

1
Chapter 2

• DENSITY

2
Chapter 2-Properties of matterSection 2-1

• VOCABULARY
• Density-
• Buoy-
• Calculate-

Mass per unit Volume.
A floating object attached to the bottom to mark
something.
To answer using a math process.
3
Chapter 2-Properties of matterSection 2-1

• Key Topic of Section 2-1 is
• What is density?
• Our objective is
• Define density.

4
Chapter 2-Properties of matterSection 2-1

• 1st Main Idea is
• Density
• Density is the ____________________
  ________________________________.

5
Chapter 2-Properties of matterSection 2-1

• 1st Main Idea is
• Density
• Density is the mass per unit volume of a
  substance.
• Discuss Fig. 2-2 on p.34.
• Video Density Definition-
• It's Chemical Density in Liquids. AIMS
  Multimedia(1989). Retrieved October 4, 2006,
  fromunitedstreaming http//www.unitedstreaming.c
  om/

6
Chapter 2-Properties of matterSection 2-1

• 2nd Main Idea is
• Units of Density
• Mass is measured in ______________.

7
Chapter 2-Properties of matterSection 2-1

• 2nd Main Idea is
• Units of Density
• Mass is measured in grams.
• The volume of solids is measured in
  ________________________________.

8
Chapter 2-Properties of matterSection 2-1

• 2nd Main Idea is
• Units of Density
• Mass is measured in grams.
• The volume of solids is measured in cubic
  centimeters.
• The volume of liquids is measured in
  ________________________________.

9
Chapter 2-Properties of matterSection 2-1

• 2nd Main Idea is
• Units of Density
• Mass is measured in grams.
• The volume of solids is measured in cubic
  centimeters.
• The volume of liquids is measured in milliliters.
• Discuss Fig. 2-3 on p.34.

10
Chapter 2-Properties of matterSection 2-1

• 2nd Main Idea is
• Units of Density
• One _____________________ is equal to one
  __________________________.

11
Chapter 2-Properties of matterSection 2-1

• 2nd Main Idea is
• Units of Density
• One milliliter is equal to one cubic centimeter.
• The density of any substance can be given in
  ____________ per _________ ________________, or
  g/cm3. (We call this a label)

12
Chapter 2-Properties of matterSection 2-1

• 2nd Main Idea is
• Units of Density
• One milliliter is equal to one cubic centimeter.
• The density of any substance can be given in
  grams per cubic centimeter, or g/cm3. (We call
  this a label)
• Discuss Fig. 2-3 on p.34.
• Video Density of Water Alcohol-
• It's Chemical Density in Liquids. AIMS
  Multimedia(1989). Retrieved October 4, 2006,
  fromunitedstreaming http//www.unitedstreaming.c
  om/

13
Chapter 2-Properties of matterSection 2-1

• 3rd Main Idea is
• Using Density
• Density is a ___________ __________ of matter.

14
Chapter 2-Properties of matterSection 2-1

• 3rd Main Idea is
• Using Density
• Density is a physical property of matter.
• The density of a ______ ____________ is always
  the same does not depend on __________ or
  _________. Ex. Lead is 11.3 g/cm3

15
Labels for mass, volume and density ( to the tune
of Im glad I am a girls scout.)

• (Chorus) I need to know the label of volume if
  you please,
• It is milliliters or centimeters 3.
• Verse 1- (6x4) But the mass is kilograms or
  grams.
• But the mass is kilograms or grams
• Verse 2 ooga chuga ooga chuga- density
• Ooga chuga ooga chuga g by cm3

16
Density practice

• 1.The density of Ivory soap is 0.9g/cm3 and the
  mass is 100 g. What is the volume?
• m/dv 100/0.9 111.1cm3
• 2. The density of zinc is 7.13g/cm3. If I have 50
  grams of it will it fit into a 50 ml container?
• m/dv 50/7.13 7 cm3 yes it will fit ( if the
  pieces are the right shape)
• 3. The density of oxygen is 0.0013g/cm3 if I
  have a container with a 500 cm3 capacity filled
  with pure oxygen what would the mass of that
  oxygen be?
• Mdv 0.0013 x 500 0.65g

17

• A lead ball has a mass of 454 g. The density of
  lead is 11.35 g/cm3. What is the ball's volume?
• What is the mass of a bar of gold that measures
  15 cm 8 cm 4 cm and has a density of
• 19.32 g/cm3?

18
Chapter 2-Properties of matterSection 2-1

• 3rd Main Idea is
• Using Density
• Density is a physical property of matter.
• The density of a pure substance is always the
  same does not depend on size or shape.
• Ex. Lead is 11.3 g/cm3
• Density can be used to ___________ different
  kinds of matter.

19
Chapter 2-Properties of matterSection 2-1

• 3rd Main Idea is
• Using Density
• Density is a physical property of matter.
• The density of a pure substance is always the
  same does not depend on size or shape.
• Ex. Lead is 11.3 g/cm3
• Density can be used to identify different kinds
  of matter.

20
Chapter 2-Properties of matterSection 2-1

• Questions from textbook (Write in packet)
• DEFINE What is density?
• Mass per unit volume of a substance
• 2. IDENTIFY In what units is density measured?
• g/cm3 (grams per cubic centimeter).
• 3. IDENTIFY What kind of property is density?
• A physical property.

21
Chapter 2-Properties of matterSection 2-1

• HOMEWORK
• p. 35, 1-6 (7 8 extra credit) Section 2-1
  Worksheet.

22
Chapter 2-Properties of matterSection 2-2

• VOCABULARY
• Express-
• Exert-

To represent in words or symbols.
To put forth an effort.
23
Chapter 2-Properties of matterSection 2-2

• Key Topic of Section 2-2 is
• How is density measured?
• Our objective is
• Explain how to find density of a solid or a
  liquid.

24
Chapter 2-Properties of matterSection 2-2

• 1st Main Idea is
• Finding Density
• You can find density by ____________ the
  _________ by the ______________.

25
Chapter 2-Properties of matterSection 2-2

• 1st Main Idea is
• Finding Density
• You can find density by dividing the mass by the
  volume.
• D m/v
• Discuss the pyramid equation (Draw it in your
  notes here)

26
Chapter 2-Properties of matterSection 2-2

• 2nd Main Idea is
• Density of a Liquid
• Steps to find the density of a liquid using a
  graduated cylinder and a balance

27
Chapter 2-Properties of matterSection 2-2

• 2nd Main Idea is
• Density of a Liquid
• Steps to find the density of a liquid using a
  graduated cylinder and a balance
• Find the mass of the graduated cylinder record.
• Add liquid to g.c. Record the volume.
• Place g.c. w/ liquid on the balance record
  mass.
• Find the mass of the liquid by subtracting the
  mass of empty g.c. from the mass of the g.c. w/
  liquid.
• Calculate by dividing the mass of the liquid by
  the volume of the liquid.
• REMEMBER In this example, density is expressed
  in g/mL, 1 mL 1 cm3.

28
Chapter 2-Properties of matterSection 2-2

• 3rd Main Idea is
• Density of a Solid
• You can use a ____________________ to find
  the_______________ of a solid.

29
Chapter 2-Properties of matterSection 2-2

• 3rd Main Idea is
• Density of a Solid
• You can use a balance to find the mass of a
  solid.
• If the solid is a ____________________, its
  volume is equal to length x width x height.

30
Chapter 2-Properties of matterSection 2-2

• 3rd Main Idea is
• Density of a Solid
• You can use a balance to find the mass of a
  solid.
• If the solid is a rectangular shape its volume is
  equal to length x width x height.
• The formula for Volume is
• V _____________________.

31
Chapter 2-Properties of matterSection 2-2

• 3rd Main Idea is
• Density of a Solid
• You can use a balance to find the mass of a
  solid.
• If the solid is a rectangular shape its volume is
  equal to length x width x height.
• The formula for Volume is
• V L x W x H.

32
Chapter 2-Properties of matter

• Video Comparing Density-
• It's Chemical Density in Liquids. AIMS
  Multimedia(1989). Retrieved October 4, 2006,
  fromunitedstreaming http//www.unitedstreaming.c
  om/
• Video Density of water Floating-
• It's Chemical Density in Liquids. AIMS
  Multimedia(1989). Retrieved October 4, 2006,
  fromunitedstreaming http//www.unitedstreaming.c
  om/
• Video Liquids dont mix-
• It's Chemical Density in Liquids. AIMS
  Multimedia(1989). Retrieved October 4, 2006,
  fromunitedstreaming http//www.unitedstreaming.c
  om/

33
Chapter 2-Properties of matterSection 2-2

• Questions from textbook (Write in packet)
• IDENTIFY What measurements must you make before
  you can calculate the density of a material?
• Mass volume.
• 2. EXPLAIN Why can density be measured either in
  g/cm3 or in g/mL?
• Because 1 mL 1 cm3
• 3. DESCRIBE How can you find the volume of a
  rectangular solid?
• Measure length, width height, then multiply
  them together.

34
Chapter 2-Properties of matterSection 2-2

• HOMEWORK
• p. 37, 1-6, Building Math Skills 8-10 (7
  extra credit) Section 2-2 Worksheet.

35
Chapter 2-Properties of matterSection 2-3

• VOCABULARY
• Specific Gravity-
• Hydrometer-
• Detect-

Denstiy of a substance compared with density of
water.
Device used to measure specific gravity.
To discover the nature of.
36
Chapter 2-Properties of matterSection 2-3

• Key Topic of Section 2-3 is
• What is Specific Gravity?
• Our objective is
• Explain what is meant by specific gravity.

37
Chapter 2-Properties of matterSection 2-3

• 1st Main Idea is
• Specific Gravity
• _______________ _______________ is the density of
  a substance compared with the density of water.

38
Chapter 2-Properties of matterSection 2-3

• 1st Main Idea is
• Specific Gravity
• Specific gravity is the density of a substance
  compared with the density of water.
• The density of water is 1 g/cm3.
• You can find specific gravity of a substance by
  ____________________ its density by the density
  of water.

39
Chapter 2-Properties of matterSection 2-3

• 1st Main Idea is
• Specific Gravity
• Specific gravity is the density of a substance
  compared with the density of water.
• The density of water is 1 g/cm3.
• You can find specific gravity of a substance by
  dividing its density by the density of water.
• Specific gravity has no label, the units cancel
  each other out.

40
Chapter 2-Properties of matterSection 2-3

• 2nd Main Idea is
• Measuring Specific Gravity
• A _______________ is a device used to measure the
  specific gravity of a liquid.

41
Chapter 2-Properties of matterSection 2-3

• 2nd Main Idea is
• Measuring Specific Gravity
• A Hydrometer is a device used to measure the
  specific gravity of a liquid.
• The ____________ the specific gravity, the
  ___________ it will float in a liquid.

42
Chapter 2-Properties of matterSection 2-3

• 2nd Main Idea is
• Measuring Specific Gravity
• A Hydrometer is a device used to measure the
  specific gravity of a liquid.
• The higher the specific gravity, the higher it
  will float in a liquid.

43
Diagram of Hydrometer
http//www.fallbright.com/web4hydrometer.gif
44
Chapter 2-Properties of matterSection 2-3

• 3rd Main Idea is
• Uses of Specific Gravity
• Specific gravity can be used to identify ______
  ______________, because each substance has a
  particular specific gravity.

45
Chapter 2-Properties of matterSection 2-3

• 3rd Main Idea is
• Uses of Specific Gravity
• Specific gravity can be used to identify pure
  substances, because each substance has a
  particular specific gravity.
• Hydrometers are used to test ________ _________
  in laboratories.

46
Chapter 2-Properties of matterSection 2-3

• 3rd Main Idea is
• Uses of Specific Gravity
• Specific gravity can be used to identify pure
  substances, because each substance has a
  particular specific gravity.
• Hydrometers are used to test blood urine in
  laboratories.
• Industries us specific gravity to check the
  ___________ of their products.

47
Chapter 2-Properties of matterSection 2-3

• 3rd Main Idea is
• Uses of Specific Gravity
• Specific gravity can be used to identify pure
  substances, because each substance has a
  particular specific gravity.
• Hydrometers are used to test blood urine in
  laboratories.
• Industries us specific gravity to check the
  purity or quality of their products.
• Discuss specific uses from our text.

48
Chapter 2-Properties of matterSection 2-3

• Questions from textbook (Write in packet)
• 1. DEFINE What is specific gravity?
• The density of a substance compared with the
  density of water.
• 2. EXPLAIN What determines the height at which a
  hydrometer floats?
• The specific gravity of a substance.
• 3. NAME What are some uses of specific gravity?
• Check purity, quality of products or blood
  urine.

49
Chapter 2-Properties of matterSection 2-3

• HOMEWORK
• p. 39, 1-8, (NO extra credit) Section 2-3
  Worksheet.

50
Chapter 2-Properties of matterSection 2-4

• VOCABULARY
• Displacement-

The replacement, or pushing aside of a volume of
water, or any fluid, by an object.
51
Chapter 2-Properties of matterSection 2-4

• Key Topic of Section 2-4 is
• What is Displacement?
• Our objective is
• 1. Define Displacement.
• 2. Find the volume of an irregular solid.

52
Chapter 2-Properties of matterSection 2-4

• 1st Main Idea is
• Displacement
• _________________________ was a Greek scientist
  about 2000 years ago.

http//money.cnn.com/2006/03/16/news/economy/annie
/fortune_annie0317/bathtub.03.jpg
53
Chapter 2-Properties of matterSection 2-4

• 1st Main Idea is
• Displacement
• Archimedes was a Greek scientist about 2000 years
  ago.
• When objects are placed in water, they make the
  water level ______________.

54
Chapter 2-Properties of matterSection 2-4

• 1st Main Idea is
• Displacement
• Archimedes was a Greek scientist about 200 years
  ago.
• When objects are placed in water, they make the
  water level rise (go up).
• _________________ is the replacement of a volume
  of water by an object.

55
Chapter 2-Properties of matterSection 2-4

• 1st Main Idea is
• Displacement
• Archimedes was a Greek scientist about 200 years
  ago.
• When objects are placed in water, they make the
  water level rise (go up).
• Displacement is the replacement of a volume of
  water by an object.

56
Chapter 2-Properties of matterSection 2-4

• 2nd Main Idea is
• Displacement Volume
• When an object is placed completely under water,
  the ______________ of the water displaced is
  equal to the ______________ of the object.

57
Chapter 2-Properties of matterSection 2-4

• 2nd Main Idea is
• Displacement Volume
• When an object is placed completely under water,
  the volume of the water displaced is equal to the
  volume of the object.
• Many objects do not have a _________ _________.

58
Chapter 2-Properties of matterSection 2-4

• 2nd Main Idea is
• Displacement Volume
• When an object is placed completely under water,
  the volume of the water displaced is equal to the
  volume of the object.
• Many objects do not have a regular shape.

59
Chapter 2-Properties of matterSection 2-4

• 2nd Main Idea is (Continued)
• Displacement Volume
• You can use displacement to find the volume of an
  irregularly shaped object (a rock)

60
Chapter 2-Properties of matterSection 2-4

• 2nd Main Idea is (Continued)
• Displacement Volume
• You can use displacement to find the volume of an
  irregularly shaped object (a rock)
• Add water to a g.c. or a beaker.
• Record the volume of the water.
• Carefully place object in the g.c. or beaker.
• Record the new volume.
• Subtract to find the volume of the object.

61
Chapter 2-Properties of matterSection 2-4

• Questions from textbook (Write in packet)
• 1. DEFINE What is displacement?
• The pushing aside of a volume of water by an
  object.
• 2. EXPLAIN How can you find the volume of an
  irregularly shaped object?
• Submerge the object in water and measure the
  amount of water that it displaces.

62
Chapter 2-Properties of matterSection 2-4

• HOMEWORK
• p. 41, 1-5, Building Math Skills a, b, c (6 7
  extra credit) Section 2-4 Worksheet.

63
Chapter 2-Properties of matterSection 2-5

• VOCABULARY
• Buoyancy-
• newton-

Tendency of an object to float in a fluid.
SI unit of force.
64
Chapter 2-Properties of matterSection 2-5

• Key Topic of Section 2-5 is
• What is Buoyancy?
• Our objective is
• Explain Archimedes Principle in terms of
  buoyancy displacement.

65
Chapter 2-Properties of matterSection 2-5

• 1st Main Idea is
• Archimedes Principle
• _________________ ______________ states that the
  weight lost by an object in water is equal to
  the weight of the water displaced by the object.

66
Chapter 2-Properties of matterSection 2-5

• 1st Main Idea is
• Archimedes Principle
• Archimedes Principle states that the weight lost
  by an object in water is equal to the weight of
  the water displaced by the object.
• Video Buoyancy-
• Dr. Dad's PH3 Episode Two Buoyancy. Louisiana
  Public Broadcasting(1995). Retrieved October 5,
  2006, fromunitedstreaming http//www.unitedstrea
  ming.com/

67
Chapter 2-Properties of matterSection 2-5

• 2nd Main Idea is
• Buoyancy
• Water exerts an _________ force on an object.
  This opposes the downward pull of _________ on an
  object, thus __________ its weight.

68
Chapter 2-Properties of matterSection 2-5

• 2nd Main Idea is
• Buoyancy
• Water exerts an upward force on an object. This
  opposes the downward pull of gravity on an
  object, thus decreasing its weight.
• _____________ is the tendency of an object to
  float in a fluid.

69
Chapter 2-Properties of matterSection 2-5

• 2nd Main Idea is
• Buoyancy
• Water exerts an upward force on an object. This
  opposes the downward pull of gravity on an
  object, thus decreasing its weight.
• Buoyancy is the tendency of an object to float in
  a fluid.
• ___________ are gases, such as air, or liquids,
  such as water.

70
Chapter 2-Properties of matterSection 2-5

• 2nd Main Idea is
• Buoyancy
• Water exerts an upward force on an object. This
  opposes the downward pull of gravity on an
  object, thus decreasing its weight.
• Buoyancy is the tendency of an object to float in
  a fluid.
• Fluids are gases, such as air, or liquids, such
  as water.

71
Chapter 2-Properties of matterSection 2-5

• 3rd Main Idea is
• Buoyancy Archimedes Principle
• Buoyancy and ________________ are related.

72
Chapter 2-Properties of matterSection 2-5

• 3rd Main Idea is
• Buoyancy Archimedes Principle
• Buoyancy and displacement are related.
• The buoyant (upward) force on an object is water
  is equal to the weight of the water that the
  object displaces. (See Fig. 2-19, p.44-show on
  marker board)

73
Chapter 2-Properties of matterSection 2-5

• 3rd Main Idea is (Continued)
• Buoyancy Archimedes Principle
• The __________ is the SI unit for force. Its
  label is (N).

74
Chapter 2-Properties of matterSection 2-5

• 3rd Main Idea is (Continued)
• Buoyancy Archimedes Principle
• The newton is the SI unit for force. Its label
  is (N).
• One kilogram is equal to 9.8 N (newtons).

75
Chapter 2-Properties of matterSection 2-5

• 4th Main Idea is
• Floating
• Buoyancy explains why an object ______________ or
  ______________.

76
Chapter 2-Properties of matterSection 2-5

• 4th Main Idea is
• Floating
• Buoyancy explains why an object sinks or floats.
• If the weight of the water displaced is to the
  weight of the object, it ________.

77
Chapter 2-Properties of matterSection 2-5

• 4th Main Idea is
• Floating
• Buoyancy explains why an object sinks or floats.
• If the weight of the water displaced is to the
  weight of the object, it floats.
• An object will ___________ if its weight is
  greater than the buoyant force.

78
Chapter 2-Properties of matterSection 2-5

• 4th Main Idea is
• Floating
• Buoyancy explains why an object sinks or floats.
• If the weight of the water displaced is to the
  weight of the object, it floats.
• An object will sink if its weight is greater than
  the buoyant force.

79
Chapter 2-Properties of matterSection 2-5
Greater
Less
Buoyant Force
Same
Weight of the object
Less
Greater
80
Chapter 2-Properties of matterSection 2-5

• Questions from textbook (Write in packet)
• 1. STATE What does Archimedes Principle state?
• The weight lost by an object is equal to the
  weight of the water displaced.
• 2. DEFINE What is buoyancy?
• Tendency of an object to float in water.
• 3. APPLY If a buoyant force of 6N acts on a
  block placed in water, what is the weight of the
  water that the block displaces?
• 6 N.
• 4. RECOGNIZE When will an object float in water?
  
• When the weight of the displaced water equals
  the objects weight.

81
Chapter 2-Properties of matterSection 2-5

• HOMEWORK
• p.45, 1-5 (6 7 is extra credit) Section 2-5
  Worksheet.