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Name: Ayşe Eda Tarakcı
Class: 9/D 218
Partners: Aslıhan Tekinırk
Sena Sevindi
Specific Heat Capacity of Tap Water
Data Performed: March 9, 2012
Introduction:
Pure substances have fixed melting and boiling points. If we add a different substance
in a pure substance, its melting and boiling points changes. In this experiment, our goal is
measuring the temperature of tap water till it boils and then calculating its specific heat
capacity by using the formula e = mcΔT which shows what we need to know for this
experiment: mass of water and change in temperature.
Hypothesis:
If the specific heat capacity of pure water is 4000, the specific heat capacity of tap water will
be more than 4000 because its impure.
List of Equipment That We Used During The Experiment
1) A kettle – to boil water
2) A stopwatch – to control the time during heating and boiling
3) Thermometer – to measure the temperature of tap water during the whole experiment
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Procedure:
Before we started boiling the water, we measured its initial temperature and its mass which
was 0.5 liter. After writing down the values, we turned on the kettle and checked the time by
using a stopwatch until it boiled. When the kettle dried, we looked under it to learn the power
of water which was 1000 W. The values that we got from the experiment were going to help
us to calculate the specific heat capacity of tap water.
With our knowledge that we’ve already known from older classes, the values will be
changeable during all of four experiments because of the conditions.

The formula that we used during the experiment  e = mcΔT which can be also
written as energy transferred = mass x specific heat capacity x change in temperature.
According to this table, boiling points and times are different, so the experiment has been
repeated for three times to find nearest value.
According to our formula which is energy transferred = mass x specific heat capacity x
change in temperature, we calculated the specific heat capacity of tap water.
For the 1st experiment:
e = mcΔT
0.5 x c x 76 = e
If e = change in time x power of kettle, it’s equal to 210 s x 1000 W.
38 x c = 210000
2
210000/38 = c
So c = 5526
For the 2st experiment:
e = mcΔT
0.5 x c x 82= 235 x 1000
41 x c = 235000
2350000/41 = c
So c = 5731
For the 3st experiment:
e = mcΔT
0.5 x c x 82 = 227 x 1000
41 x c = 227000
227000/41 = c
So c = 5536
For the 4st experiment:
e = mcΔT
0.5 x c x 80 = e
40 x c = 229000
229000/40 = c
c = 5725
After finding all of the specific heat capacity values, we calculated the average.
(5526 + 5731 + 5736 + 5725) / 4 = 22518 / 4 = 5629,5 (specific heat capacity of tap water)
Conclusion:
The hypothesis was “If the specific heat capacity of pure water is 4000, the specific heat
capacity of tap water will be more than 4000 because of its impurity.” During the experiment,
we learned that impure substances have higher specific heat capacities.
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