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Material properties
Dewar flask calorimeter
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253 081
ENGLISH
3 Adiabatic properties
3.1 Thermal inertia
The melting of an ice cube in 250 ml of water lowers the temperature in the
enclosure.
Ambient temperature: 20° C
Temperature in the calorimeter after fusion: 13.3° C
The initial temperature difference between the surroundings and the
calorimetric enclosure is 6.7° C.
time
0
1 h
T (° C)
13.3
14.2
∆T(° C)
0
0.9
As calorimetric experiments last only a few minutes, we can consider that the
calorimeter is perfectly adiabatic (insulated) for a temperature difference of ±
5° C between the ambient and internal temperatures.
3.2 Heat loss
We have established the heat loss curve of the calorimeter with 200 g of
water, the ambient temperature being 25° C
7
2 h
3 h
4 h
14.9
15.5
16
1.6
2.2
2.7
.
5 h
7 h
10 h
16.3
17
17.5
3.0
3.7
4.2
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