Chapter 6 Energy and States of Matter

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Chapter 6Energy and States of Matter

• Energy
• Measuring Temperature

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Energy

• Makes objects move
• Makes things stop
• Energy from sun plants foods we eat
  energy to live
• We need energy to do work

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Work is done when

• Go up stairs
• Play soccer
• Lift a bag of groceries
• Ride a bicycle
• Breathe
• Heart pumps blood
• Water goes over a dam

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Potential Energy

• Is stored energy
• Examples
• Water behind a dam
• Compressed spring
• Chemical bonds in gasoline or coal
• Food

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Kinetic Energy

• Is energy of motion
• Examples
• Hammering a nail
• Water flowing over a dam
• Working out
• Boxing
• Burning gasoline

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Some Forms of Energy

• Mechanical
• Electrical
• Thermal (heat)
• Chemical
• Radiant (light)

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Learning Check E1

• A. A car uses more fuel when the air
• conditioner is on.
• True (1) or False (2)
• B. An apple hanging on a tree has potential
• energy that can turn into both mechanical
• or chemical energy.
• True (1) or False (2)

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Solution E1

• A. A car uses more fuel when the air conditioner
  is on. True (1)
• B. An apple hanging on a tree has potential
  energy that can turn into both mechanical or
  chemical energy. True(1)

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Temperature

• Particles are always moving.
• When you heat water, the water molecules move
  faster.
• When molecules move faster, the substance gets
  hotter.
• When a substance gets hotter, its temperature
  goes up.

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Learning Check E2

• Suppose you place water in a freezer.
• A. The water particles move
• 1) faster 2) slower 3) the same
• B. The water will get
• 1) hotter 2) colder 3) stay the same
• C. The temperature of the water will be
• 1) higher 2) lower 3) the same

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Solution E2

• Suppose you place water in a freezer.
• A. The water particles move
• 2) slower
• B. The water will get
• 2) colder
• C. The temperature of the water will be
• 2) lower

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Temperature

• Measures the hotness or coldness of an object
• Determined by using a thermometer that contains a
  liquid that expands with heat and contracts with
  cooling.

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Temperature Scales
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Temperature Scales

• Fahrenheit Celsius Kelvin
• Water boils 212F 100C 373
  K
• Water freezes 32F 0C 273
  K

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Units of Temperature between Boiling and Freezing

• Fahrenheit Celsius Kelvin
• Water boils 212F 100C 373
  K
• 180 100C 100K
• Water freezes 32F 0C 273
  K

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Learning Check E3

• A. Temperature of freezing water
• 1) 0F 2) 0C 3) 0 K
• B. Temperature of boiling water
• 1) 100F 2) 32F 3) 373K
• C. Number of Celsius units between the
• boiling and freezing points of water
• 1) 100 2) 180 3) 273

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Solution E3

• A. Temperature of freezing water
• 2) 0C
• B. Temperature of boiling water
• 3) 373K
• C. Number of Celsius units between the
• boiling and freezing points of water
• 1) 100

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Fahrenheit Formula

• 180F 9F 1.8F 100C
  5C 1C
• Zero point 0C 32F
• F 9/5 TC 32
• or
• F 1.8 TC 32

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Celsius Formula

• Rearrange to find TC
• F 1.8 TC 32
• F - 32 1.8TC ( 32 - 32)
• F - 32 1.8 TC
• 1.8 1.8
• F - 32 TC
• 1.8

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Temperature Conversions

• A person with hypothermia has a body temperature
  of 29.1C. What is the body temperature in F?
• F 1.8 (29.1C) 32
• exact tenth's
  exact
• 52.4 32
• 84.4F
• tenths

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Learning Check E4

• The normal temperature of a chickadee is
  105.8F. What is that temperature in C?
• 1) 73.8 C
• 2) 58.8 C
• 3) 41.0 C

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Solution E4

• 3) 41.0 C
• Solution
• C (F - 32)
• 1.8
• (105.8 - 32)
• 1.8
• 73.8F
• 1.8 41.0C

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Learning Check E5

• Pizza is baked at 455F. What is that in C?
• 1) 437 C
• 2) 235C
• 3) 221C

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Solution E5

• Pizza is baked at 455F. What is that in C?
• 2) 235C
• (455 - 32) 235C
• 1.8

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Learning Check E6

• On a cold winter day, the temperature falls to
  -15C. What is that temperature in F?
• 1) 19 F
• 2) 59F
• 3) 5F

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Solution E6

• 3) 5F
• Solution
• F 1.8(-15C) 32
• -27 32
• 5F

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Kelvin Scale

• On the Kelvin Scale
• 1K 1C
• 0 K is the lowest temperature
• 0 K - 273C
• K C
• K C 273

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Learning Check E7

• What is normal body temperature of 37C in
  kelvins?
• 1) 236 K
• 2) 310 K
• 3) 342 K

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Solution E7

• What is normal body temperature of 37C in
  kelvins?
• 2) 310 K
• K C 273
• 37 C 273
• 310. K