Heat Change calculations worksheet

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Name ___________________________Group __________________
Period __________
Heat Change calculations worksheet #2
1. Aluminum has a specific heat of 0.902 J/g oC. Calculate how much heat is
lost when a piece of aluminum with a mass of 23.98 g cools from a temperature
of 415.0 oC to a temperature of 22.0 oC?
2. The temperature of a sample of water increases by 69.5 oC when 24 500 J are
applied. The specific heat of liquid water is 4.18 J/g oC. What is the mass of
the sample of water?
3. 850 calories of heat are applied to a 250 g sample of liquid water with an initial
temperature of 13.0 oC. Remember, the specific heat of liquid water, in calories,
is 1.00 cal/g oC.)
a. Find the change in temperature of the water.
b. Calculate the final temperature of the water.
4. When 34 700 J of heat are applied to a 350 g sample of an unknown material
the temperature rises from 22.0 oC to 173.0 oC. What must be the specific heat
of this material?
Name ___________________________Group __________________
Period __________
5. Calculate the total heat energy (in cal) that is required to cool 127 g of water
vapor from 125˚C to ice at -15˚C. Remember ΔH vap = 540 cal/g, ΔH fus = 80
cal/g, C vapor = 0.4 cal/g oC, C water = 1.0 cal/g oC, C ice = 0.5 cal/g oC.
6. A student wanted to determine the specific heat capacity of an unknown metal,
X. She heated the metal in hot water and then immediately transferred it to 150
ml of cold water. The temperature change of the cold water was recorded. Here
lab data is shown below:
Table 1 – Determination of Specific Heat Capacity of Unknown Metals
Start temp. of
Start temp.
End temp. of
Substance
Mass (g)
O
substance ( C) of cold water substance and
(OC)
water (OC)
26.2
X
72 g
92.3 ˚C
24.0 ˚C
˚C
a) Complete the results table below for substance X.
Table 2 – Calculations of Specific Heat Capacity of Unknown Metals
Substance
Temp.
Heat
Mass of
Temp.
change of
absorbed
substance
change of
water (OC)
by water
(g)
substance
(lost by
(OC)
substance)
(cal)
X
Specific
heat
capacity of
substance
(cal/g•OC)
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