WS D-2: Energy Transformations & Heat Capacity
Name ________________
1. Which has more heat: West Hawk Lake in June or a cup of boiling water? Explain your
answer.
2. What always happens when two object of different temperatures come into contact?
Give an example from your daily life.
3. Classify these process as exothermic or endothermic:

Condensing steam

Evaporating alcohol

Burning alcohol

Baking a potato
4. Energy always flows from _______ to _____________.
5. When you open your door in the winter and your mom says: “Quit letting the cold in the
house,” what should you politely tell her?
Substance
Heat
Capacity
(J/gºC)
4.18
Substance Heat
Capacity
(J/gºC)
Water
Grain
2.4
Alcohol
Ice
2.1
Steam
1.7
Chloroform 0.96
Aluminum 0.90
Glass
0.50
Iron
0.46
Silver
0.24
Mercury
0.14
Lithium
0.14
Copper
0.39
Uranium
0.12
Gold
0.13
Use the table above to answer the following questions and the following formula:
Q= (m)(c)(ΔT)
Where:
Q = quantity of energy(J)
m = mass(g)
c = specific heat capacity (J/gºC)
ΔT = change in temperature (ºC)
6. A 75.0g sample of a metal at 98.0º C is dropped into a container of 350. g of water at
24.0ºC, The final temperature is 24.5 ºC. What is the specific heat of the metal?
7. A 55.0 g sample of a metal at 90.0º C is dropped into a container of 250. g of water at
22.0ºC, The final temperature is 23.4 ºC. What is the metal?
8. A 200.0 g sample of a metal at 92.0º C is dropped into a container of 100. g of water at
26.0ºC, The final temperature is 45.6 ºC. What is the metal? What is the percentage
error?
WS D-2: Energy Transformations & Heat Capacity
Name ________________
1. Which has more heat: West Hawk Lake in June or a cup of boiling water? Explain your
answer. West Hawk Lake. Heat is TOTAL energy—and you have a massive amount of
water molecules each with a little energy in the lake . As oppose to a small amount of
molecules each with a lot of energy in the cup.
2. What always happens when two object of different temperatures come into contact?
Give an example from your daily life. Heat will transfer from high temp to low until
equilibrium is established. A cup of hot coffee goes to room temp as the heat is
transferred out of the cup into the colder air. Thus you have to reheat your coffee or
drink it fast!
3. Classify these process as exothermic or endothermic:
*remember that exothermic the reactants are high energy than products. Endothermic the
reactants are lower energy than products. States of matter: solid is lowest energy liquid is
middle, and gas is the highest energy state
 Condensing steam
Go from high energy gas to lower energy liquid: exothermic
 Evaporating alcohol
Go from low energy liquid to higher energy vapor: endothermic
 Burning alcohol
Not a phase change here, so use other logic. Anytime you hear the word
“burning” heat release should come to mind: exothermic
 Baking a potato
Cooking involves the addition of a lot of heat: endothermic
4. Energy always flows from ___hot____ to ______cold_______.
5. When you open your door in the winter and your mom says: “Quit letting the cold in the
house,” what should you politely tell her?
My dear, lovely, brilliant, youthful mother; let me correct your minor error. The direction
energy flows is from hot to cold—so technically we would be heating the outdoors.
However, many gifted brilliant people have made this error so you are in good company.
Worksheet D
Name:
Period
Substance
Heat
Capacity
(J/gºC)
4.18
Substance Heat
Capacity
(J/gºC)
Water
Grain
2.4
Alcohol
Ice
2.1
Steam
1.7
Chloroform 0.96
Aluminum 0.90
Glass
0.50
Iron
0.46
Silver
0.24
Mercury
0.14
Lithium
0.14
Copper
0.39
Uranium
0.12
Gold
0.13
Use the table above to answer the following questions and the following formula:
Q= (m)(c)(ΔT)
Where:
Q = quantity of energy(J)
m = mass(g)
c = specific heat capacity (J/gºC)
ΔT = change in temperature (ºC)
A 75.0g sample of a metal at 98.0º C is dropped into a container of 350. g of water at
24.0ºC, The final temperature is 24.5 ºC. What is the specific heat of the metal?
Qmetal = -QH2O
(75.0 g)(c)(98.0 oC-24.5 oC) = (350.g)(4.18 J/g oC)(24.5 oC -24 oC)
C= .133 J/g oC
6. A 55.0 g sample of a metal at 90.0º C is dropped into a container of 250. g of water at
22.0ºC, The final temperature is 23.4 ºC. What is the metal?
(55.0 g)( c ) (90.0 oC -23.4 oC) = (250.g)(4.18 J/g oC)(23.4 oC – 22.0 oC)
C = .399J/goC from the chart above, the metal is Copper
7. A 200.0 g sample of a metal at 92.0º C is dropped into a container of 100. g of water at
26.0ºC, The final temperature is 45.6 ºC. What is the metal? What is the percentage
error?
(200.0g) c (92-45 oC.6 oC) = (100.g)(4.18 J/g oC)(45.6 oC -26.0 oC)
C= .883 J/goC which is closest to aluminum
% Error = difference between actual and experimental value/actual value x 100
=.90 - .883/.90 x 100 = 1.89 %