Lab: Determination of the Heat of Fusion of Ice
Purpose: In this lab, you will determine experimentally the heat of fusion of ice, ΔHfus. This
is the amount of heat energy required to melt 1.00 g ice at its melting point of 0.00 oC.
Procedure
1. Determine the mass of a clean, dry styrofoam cup.
2. Add enough tap water to the styrofoam cup to about 1/2 full.
3. Determine the mass of the styrofoam cup and the water. Subtract the mass of the cup from
the mass of the cup and water. Record the mass of the water alone in the Data Table as M1.
Remove the styrofoam cup with water from the balance.
4. Immediately measure the temperature of the water in the styrofoam cup as accurately as
possible and record this initial temperature as T1 in the DataTable.
5. IMMEDIATELY add 2-3 ice cubes to the water in the Styrofoam cup and begin stirring
gently with the thermometer. Stir continuously! As the last of the ice appears about to melt,
add another ice cube. The cup should contain ice at all times.
6. Continue stirring and adding ice as needed until the temperature of the water/ice mixture no
longer decreases. It should be less than 4⁰C. Record this final temperature as T2 in the Data
Table.
7. Using tongs, carefully remove the unmelted ice – allow as much water as possible to drip
from the unmelted ice into the styrofoam cup. Place the unmelted ice into the sink.
8. Mass the water that is now in the styrofoam cup. Subtract the mass of the empty dry cup
from the mass of the cup and water. Record this final mass of the water alone as M2 in the
Data Table.
9. Repeat Steps 1 – 8 for one more trial.
1
DATA TABLE
Mass of
clean, dry
styrofoam
cup (g)
Original
Mass of
Water
(g)
(M1)
Mass
Final Mass of
of Water (g) Melted
Ice
(M2)
(g)
Trial
#
Initial
Water
Temp
(oC)
Final
Water
Temp
(oC)
Change
in
Temp
(oC)
(T1)
(T2)
(T)
(M2 
M1)
1
2
Calculations (Do these for both trials)
1. How much heat was lost by the water?
2. How much heat was gained by the ice? How do you know this? (No calculation
required!)
3. Calculate the heat of fusion of ice in J/g.
4. Calculate the heat of fusion of ice in kJ/mol.
5. Calculate your percent error using the accepted value for the molar heat of fusion (6.01
kJ/mol).
Post Lab Questions
1. Using evidence from this lab, explain how calorimetry is a demonstration of the law of
conservation of energy.
2. a) Is the process of melting endothermic or exothermic?
b) State evidence from this lab to support your answer.
3. How much heat is required to melt 10.5 g of ice at 0⁰C?
Conclusion
2