Heat of Fusion of Ice
Objective : Determine the (molar) heat of fusion of ice.
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Procedure :
(1) Start a hot water bath (~60C) using a 250mL beaker and a hot plate. Place a 50mL (or
100mL) graduated cylinder upside down in the water bath to warm it.
(2) Fill a calorimeter (two Styrofoam cups together) halfway with ice.
 What is the ‘job’ of a calorimeter?
(3) Measure the temperature of warm water.
(4) Pour ~30mL of warm water into the warm graduated cylinder and quickly measure the
volume.
 What is going on in terms of energy as you are measuring the volume?
(5) Once the volume is measured, quickly pour into the calorimeter. (Make sure it contains
only ice, no liquid water, before warm water is added.)
 Which data would it make inaccurate if calorimeter has significant amount of liquid
water at this point?
(6) While using the thermometer as a stirrer, read the temperature(s).
 What do you expect the temperature to read?
 What is (are) losing energy?
 What is (are) gaining energy?
(7) Before all ice sample melts and when the final temperature reads around 0 C, pour the
water back into the graduated cylinder and measure the volume.
* What causes the volume difference between step (4) and step (7)?
* If the final temperature is reading 20.0C, is that the final temperature of warm water
or final temperature of melted ice once they melted, or both?
*What is the advantage of having the final temperature to be 0.0C ?
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Prelab Questions :
(PL1) What is the amount of heat lost in KJ for 50.mL of water going from 70.0C to 1.0C?
(PL2) If all the heat from previous question went to melt 30.0g of ice, what is the heat of
fusion of ice in KJ/g? KJ/mol?
(PL3) What are you assuming the initial temperature of ice is when you did (PL2)?
Analysis:
(A1) Calculate the volume of ice melted.
(A2) Calculate the heat lost by warm water using 4.184J / g K as the specific heat of liquid
water.
(A3) Calculate the heat of fusion of ice in kJ/g and calculate the molar heat of fusion of ice
in kJ/mol.
Questions:
(Q1) What would happen to the final result (what is the final answer?) if the graduated
cylinder were colder than the water sample in step (4)?
(Q2) What would happen to the final result if the graduated cylinder were colder than the
water sample in step (7)?
(Q3) What would happen to the final result if you read the volume very slowly in step #4 and
waited a long time before pouring into the calorimeter in step #5?
(Q4) What would happen to the final result if the ice you had in the calorimeter was actually
at less than 0.0C?
(Q5) For this lab (amount of heat lost by warm water ) = (amount of heat gained to melt the
ice) when there was some ice left in the mixture and the final temperature was close to 0.0C.
Write similar equation (not number crunching!) if the final temperature was 5.0C and there
was no ice left (you waited too long so all the ice melted and the temperature of the mixture
went up to 5.0C).
Summary :
Volume of warm water _______
Volume of melted ice_______
Initial temperature of warm water ___
final temperature of the mixture _____
H for warm water ________
H for ice _______
heat of fusion _________
Theoretical heat of fusion _________
molar heat of fusion _________
theoretical molar heat of fusion _________