ITU Termodynamics Lab Report

1. PHYSICS ENGINEERING DEPARTMENT
FIZ341E - Statistical Physics and Thermodynamics
Laboratory
Name of Exp. : Fusion Latent Heat of Water
Date of Exp. : 15.10.2014
BARIŞ ÇAKIR
090100235

2. Introduction
In Fusion latent heat of water experiment we observe ice cubes behavior
under phase-change. When ice cubes are heated, we face with phase-transition
(melting). In theory, when we heat the ice cubes temperature raises till 0 C, then
phase-transition begins. In melting phase temperature remains at 0 C (figure1.),
but we are still heating the cubes. Theory explains this situation with hidden
heat. Hidden heat is the required heat for completing the phase transition and it
can be calculated by following formula;
=
We will calculate Latent Heat of Water (in fusion) which is already know
before, and compare measured L value and literature’s L value also we are
expecting to observe constant heat at phase transition (B).
Figure1. Temperature versus time (in phase transition)
Experimental Procedure
Tools and devices: A calorimeter vessel, a balance, a thermometer, a
kettle, some water, 3 ice cubes
Procedure: We heated the water at 100 C and pour it into the calorimeter
vessel with help of the kettle. We waited till heat drop stops then we put 3 cubes
of ice in to the calorimeter vessel and again we waited for equilibrium heat. We
calculated weight of ice cubes and water with balance also we measured 2

3. equilibrium heat with thermometer. With following constants and equation we
calculate ‘latent heat for solid to liquid phase change of water’;
=
1
, =
30
=
( − ) + ( − ) −
= 79,79 /
Data Analysis
Temperature when the heat transformation between the vessel and water
stops;
= 79
Mass of water;
= 203,30
Equilibrium temperature of ice-water mix;
= 58
Mass of ice cubes;
= 24,45
If we put these values to the L equation which given at below, latent heat
(L) will be;
=
30 16 + 203.30 1 16 − 24.45 1 58
24.45
= 94,670 /
Conclusion
Our expectations from the experiment are;
 Constant temperature at phase transition, we observed this constant value
that’s why heat in phase transition calculated with following formula;
=

4.  Also, we know ‘heat energy taken by ice equals heat energy given by hot
water, with help of this information we checked our result by comparing
literature’s latent heat and experimental latent heat;
−
100
94,670 − 79,79
79,79
100 = %18.64
This error mostly come from water which we used at experiment is not
pure but literature calculated latent heat with pure water.
Resources
 Thermodynamics LAB FÖY
 https://www.youtube.com/watch?v=H-Rvje99XEw
 http://en.wikipedia.org/wiki/Latent_heat#Specific_latent_heat
Answers
1. There is not a phase transition so we are going to use classic equation,
= ∆
= 500 50
1
= 25
2. At B point,
= 395.7 − 62.7 = 333
From the equation which is given at conclusion part latent heat of fusion will be,
= = 333 /
At D point,
= 3037 − 813.7 = 2223.3
And latent heat of vaporization will be,
= = 2223.3 /