Worksheet Chapter 3 - 3

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Worksheet Chapter 3 - 3

• Key

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1. Which substance must have more energy removed
from it to undergo a ten degree temperature drop?
One with a low specific heat or one with a high
specific heat?
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1. Which substance must have more energy removed
from it to undergo a ten degree temperature drop?
One with a low specific heat or one with a high
specific heat?
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2. A student wants to determine the amount of
energy he will need to add to a beaker of water
in order to increase the temperature of the water
by 15C. What else must he measure before he can
determine the amount of energy required?
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2. A student wants to determine the amount of
energy he will need to add to a beaker of water
in order to increase the temperature of the water
by 15C. What else must he measure before he can
determine the amount of energy required?
He will need to measure the mass of the
water. Specific heat is needed but can be looked
up rather than measured.
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3. How much energy, in J and kJ, is required to
raise the temperature of 123.4g of aluminum metal
from 3.0ºC to 31.6 ºC? (Cp of Al 0.899 J/g ºC)
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3. How much energy, in J and kJ, is required to
raise the temperature of 123.4g of aluminum metal
from 3.0ºC to 31.6 ºC? (Cp of Al 0.899 J/g ºC)
q m?TCp
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3. How much energy, in J and kJ, is required to
raise the temperature of 123.4g of aluminum metal
from 3.0ºC to 31.6 ºC? (Cp of Al 0.899 J/g ºC)
q m?TCp (123.4g)(28.6ºC)(0.899 J/gºC)
3172.786 J
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3. How much energy, in J and kJ, is required to
raise the temperature of 123.4g of aluminum metal
from 3.0ºC to 31.6 ºC? (Cp of Al 0.899 J/g ºC)
q m?TCp (123.4g)(28.6ºC)(0.899 J/gºC)
3172.786 J 3170 J
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3. How much energy, in J and kJ, is required to
raise the temperature of 123.4g of aluminum metal
from 3.0ºC to 31.6 ºC? (Cp of Al 0.899 J/g ºC)
q m?TCp (123.4g)(28.6ºC)(0.899 J/gºC)
3172.786 J 3170 J
3.17 kJ
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4. How much energy, in J and kJ, is released
when 890.6 g of iron metal is cooled from 456ºC
to 22ºC? (CpFe 0.444 J/g ºC)
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4. How much energy, in J and kJ, is released
when 890.6 g of iron metal is cooled from 456ºC
to 22ºC? (CpFe 0.444 J/g ºC)
q m?TCp
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4. How much energy, in J and kJ, is released
when 890.6 g of iron metal is cooled from 456ºC
to 22ºC? (CpFe 0.444 J/g ºC)
q m?TCp (890.6g)(434ºC)(0.444 J/gºC)
171,615 J
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4. How much energy, in J and kJ, is released
when 890.6 g of iron metal is cooled from 456ºC
to 22ºC? (CpFe 0.444 J/g ºC)
q m?TCp (890.6g)(434ºC)(0.444 J/gºC)
171,615 J 172,000 J
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4. How much energy, in J and kJ, is released
when 890.6 g of iron metal is cooled from 456ºC
to 22ºC? (CpFe 0.444 J/g ºC)
q m?TCp (890.6g)(434ºC)(0.444 J/gºC)
171,615 J 172,000 J
172 kJ
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5. What increase in temperature will result if
212.0g of copper absorbs 4.08kJ of heat energy?
(CpCu 0.385 J/g ºC)
q m?TCp ?T q (m) (Cp) 4.08 kJ 4080 J
?T 4080J (212.0g) (0.385 J/gºC)
49.9877ºC 50.0 ºC
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1. An 83.7g sample of metal absorbs 483 J of energy
   when the temperature increases from 13.8 ºC to
   26.8 ºC. What is the specific heat of metal?

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1. An 83.7g sample of metal absorbs 483 J of energy
   when the temperature increases from 13.8 ºC to
   26.8 ºC. What is the specific heat of metal?

q m?TCp
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1. An 83.7g sample of metal absorbs 483 J of energy
   when the temperature increases from 13.8 ºC to
   26.8 ºC. What is the specific heat of metal?

q m?TCp Cp q (m) (?T)
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1. An 83.7g sample of metal absorbs 483 J of energy
   when the temperature increases from 13.8 ºC to
   26.8 ºC. What is the specific heat of metal?

q m?TCp Cp q (m) (?T) Cp q (m)
(?T) 483 J (83.7g) (13.0ºC)
0.443893 J/gºC 0.444 J/gºC
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7. A piece of unknown metal with a mass of 23.8g
is heated to 100.0C and dropped into 50.0ml
(50.0g) of water at 24.0C. The temperature of
the water rises to 32.5C. What is the specific
heat of the metal?
Water Metal
q q m?TCp m?TCp
(50.0g)(8.5ºC)(4.184 J/gºC)
(23.8g)(67.5ºC)(Cp) 1778.2 J
(23.8g)(67.5ºC)(Cp) Cp 1778.2 J
(23.8g) (67.5ºC) Cp 1.106878
J/gºC Cp 1.11 J/gºC
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8. A blacksmith heats an iron bar to 1445C.
The blacksmith then places the iron into 42800ml
of water at 22C. The temperature of the water
increases to 45C. What is the mass of the iron
bar?
Water Iron q q m?TCp
m?TCp (42800g)(23ºC)(4.184 J/gºC)
m(1400.ºC)(0.444 J/gºC) 4118729 J
m(1400.ºC)(0.444 J/gºC) m
4118729 J (1400.ºC)(0.444J/gºC) m
6626g m 6600g
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9. A geologist at a mining company is trying to
identify a metal sample. She takes 5.05g of the
unknown metal and heats it to 102.3C. She then
drops the hot metal into 13.2ml of water at
22.1C. The temperature of the water increase to
23.8C. What is the specific heat of the metal?
Water Metal q q
m?TCp m?TCp (13.2g)(1.7ºC)(4.184
J/gºC) (5.05g)(78.5ºC)(Cp) 93.8896 J
(5.05g)(78.5ºC)(Cp) Cp 93.8896 J (5.05g)
(78.5ºC) Cp 0.23684 J/gºC Cp 0.237
J/gºC
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