Chapter 1
Measuring Temperature
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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
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
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3) the same
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Solution
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
Fahrenheit Celsius
Water boils
Kelvin
_____°F
_____°C
______K
Water freezes _____°F
_____°C
______K
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Temperature Scales
Fahrenheit Celsius
Kelvin
Water boils 212°F
100°C
373 K
Water freezes 32°F
0°C
273 K
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Units of Temperature between
Boiling and Freezing
Fahrenheit Celsius
Water boils 212°F
180°
Water freezes 32°F
100°C
100°C
0°C
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Kelvin
373 K
100K
273 K
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Learning Check
A. Temperature of freezing water
1) 0°F
2) 0°C
3) 0 K
B. Temperature of boiling water
1) 100°F
2) 32°F
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
A. Temperature of freezing water
2) 0°C
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
180°F
5°C
=
Zero point:
9°F =
1°C
1.8°F
100°C
0°C = 32°F
°F
= 9/5 T°C + 32
°F
= 1.8 T°C + 32
or
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Celsius Formula
Rearrange to find T°C
°F
=
1.8 T°C + 32
°F - 32
=
1.8T°C ( +32 - 32)
°F - 32
=
1.8 T°C
1.8
°F - 32
1.8
=
T°C
1.8
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Temperature Conversions
A person with hypothermia has a body temperature
of 29.1°C. What is the body temperature in °F?
°F =
1.8 (29.1°C) + 32
exact tenth's
=
52.4 + 32
=
84.4°F
exact
tenth’s
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Learning Check
The normal temperature of a chickadee is 105.8°F.
What is that temperature in °C?
1) 73.8 °C
2) 58.8 °C
3) 41.0 °C
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Solution
3) 41.0 °C
Solution:
°C =
=
=
(°F - 32)
1.8
(105.8 - 32)
1.8
73.8°F
1.8°
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=
41.0°C
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Learning Check
Pizza is baked at 455°F. What is that in °C?
1) 437 °C
2) 235°C
3) 221°C
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Solution
Pizza is baked at 455°F. What is that in °C?
2) 235°C
(455 - 32) = 235°C
1.8
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Learning Check
On a cold winter day, the temperature falls to
-15°C. What is that temperature in °F?
1) 19 °F
2) 59°F
3) 5°F
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Solution
3) 5°F
Solution:
°F = 1.8(-15°C) + 32
= -27 + 32
= 5°F
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Kelvin Scale
On the Kelvin Scale
1K
=
1°C
0 K is the lowest temperature
0K
K
K =
= - 273°C
°C
°C + 273
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Learning Check
What is normal body temperature of 37°C in
kelvins?
1) 236 K
2) 310 K
3) 342 K
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Solution
What is normal body temperature of 37°C in
kelvins?
2) 310 K
K
=
=
=
°C + 273
37 °C + 273
310. K
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