IHSAN DOĞRAMACI FOUNDATION
BİLKENT ERZURUM LABORATORY SCHOOL
2nd Semester
2011-2012 Academic Year
9th Grade Physics
LAB REPORT 1
Name: Kayacan KAYA
Topic: Calculating the specific heat capacity of tap water
Research Question: Specific heat capacity of pure water is calculated as 4200 J/(kgoC).
However, does the specific heat capacity of normal tap water change?
Introduction:
The specific heat capacity of a substance is defined as the heat required raising unit mass of
substance by one degree of temperature.
Here is our Formula :
Where m is mass of substance, c is called specific heat capacity, and
is change in
temperature.
Aim of this experiment is to find more accurate values for specific heat capacity of tap water.
In order to find the energy transferred, this formula below may be used:
where power is known as 1000W.
Setup:
Before we start to work on the experiment, laboratory , equipments and safety should be
double-checked.
List of Equipments:
 Kettle (1000W)
 Thermometer
 Stopwatch
 Tap Water (
kg)
In order to reach more accurate results, the experiment should be repeated 4 times
(perhaps more.) For each experiment, make sure that all items are ready to be used.
Procedure to Follow:
 First of all, provide the apparatus required for the experiment.
 Fill the kettle with water. Make sure it weights ½ liters.
 Then, measure the temperature of tap water before you heat it, and note them.
 Determine a time by using stopwatch. Never let the water boil. Because when water
boils a process called evaporation which may decrease the volume of water can
appear.

After the time, measure the temperature of hot tap water and write down the data
again.

Repeat these processes for 4 times and for each time; change the time interval.

Lastly, use your datas to get find out the specific heat capacity of water.
Datas:
First Experiment:
Time:
0 second
30th second
20oC
40 oC
The specific heat capacity of tap water found in this experiment is:
Energy = 45000J
45 000 J = ½ kg x c x 20oC
C = 5000 J/kg oC
Second Experiment:
Time:
0 second
60th second
20 oC
44 oC
The specific heat capacity of tap water found in this experiment is:
1000 = energy/60
Energy = 60 000
60 000 J = ½ kg x c x 24oC
C = 5000 J/kg oC
Third Experiment:
Time:
0 second
75th second
18 oC
54 oC
The specific heat capacity of tap water found in this experiment is:
1000 = energy/75
Energy = 75 000
75 000 J = ½ kg x c x 36oC
C ~= 4166 J/kg oC
Fourth Experiment:
Time:
0 second
90th second
23 oC
63oC
The specific heat capacity of tap water found in this experiment is:
1000 = energy/90
Energy = 90 000
90 000 J = ½ kg x c x 40oC
C ~= 4500 J/kg oC
Data Result:
Experiment:
Specific Heat Capacity Found: (J/kg oC)
1st
5000 J/kg oC
2nd
5000 J/kg oC
3rd
4166 J/kg oC
4th
4500 J/kg oC
According to the experiments we have been working on , average specific heat capacity of tap
water shown below:
4666,5 J/kg oC.
Conclusion of the Experiment:
Finally, as we have found out the fact that impure water (tap water) differs from pure
water with its specific heat capacity. As we know tap water contains other elements like
minerals and chlorine which make it different from pure water. While we are working on the
experiment, amount of water should remain constant to be able to have more accurate results.
We were testing the effect of time on our experiment. Therefore , change in amount of water
could affect out variable in this experiment Also, we make sure that thermometer does not
touch the bottom of our kettle to only estimate the temperature of water not energy coming
from electricity. In order to find closer values we may repeat this experiment by using
different variables.