Name:
Katherine Beyer
Quiz Section:
BE
ID Num
1026131
Lab Partner:
David Ambramov
Total Points = 60 pts (5 notebook, 55 template)
PURPOSE AND METHOD
DATA AND CALCULATIONS
A: HEAT CAPACITY OF THE CALORIMETER
Run 1
Run 2
Run 3
Voltage, V (J/C)
3.3
3.3
3.3
Current, A (C/s)
3.11
3.1
3.1
Time
(s)
150
151
149
22.4
22.7
22.7
26.5
26.9
26.9
*Eletrical power input into calorimeter (q), J
1395
1545
1524
340.0
367.8
362.9
357
Standard Dev
15
Help
In Excel type "=average(range of values)"
Instead of entering a range, just click at one end of the values
and drag mouse to the other end.
For standard deviation, in Excel type "=stdev(range of values)".
B: HEAT OF FUSION OF ICE
Run 1
Run 2
357
357
Initial temperature,
o
C
Final temperature,
o
C
*Calorimeter Constant, C
cal,
J/
o
C
Average, C
cal
C
cal
(Average), J/
o
C
Our goals are to:
i) Determine the heat capacity of the calorimeter
In order to determine the heat capacity of the calorimeter, we need to determine the heat gained by the calorimeter over a change in temperature. In order to obtain the
heat gained by the calorimeter, we will pass a fixed current througha heat resistor. The heat gained by the caliormeter can be easily established by the equation q
cal
(J)
= curent (C/s) x Voltage (J/C) x time (s), using the information that was gathred from the experiment. The heat capacity of the calorimeter id euqal to the heat gained
divided by the change in temperature, we need to measure the initial and final temperatures. By calculating the final and initial temperatures, we can calculate the heat
capacity using the equation:
C
cal
= (q
cal
)/(ΔT) =
ii) Measure the heat of fusion of ice
To calculate the heat of fusion we know that the energy lost by the calorimeter is equal to the energy to melt ice and the heat gained by the ice/water. The heat lost by
the calorimeter can be determined by the heat capacity of the calorimeter (already determined in part i) and the change in temperature of the calorimeter. The heat
gained by the ice is determined by the mass of the ice added, the heat capacity of water and the change of temperature of the ice/water. Since the mass of the ice can
be measured as can the change in temperature of the ice/water and the capacity of water in commonly known the heat gained by ice/water can be calculated. Overall
the heat of fusion can be calculated with: (qcal) =(mice)(ΔHfusion) + (qwater/ice). Where qcal = (Ccal)(ΔTcal) = (qcal)/(Tf  Ti) and qice/water = (mice)(Cwater)
(ΔTwater/ice) = (mice)(Cwater)(Tf  Ti).
iii) Measure the heat of neautralization
By finding the heat lost by the reaction per mole of water created one can determine the heat of neutralization. To determine the moles of water, you first find the moles
of acetic acid, sodium hydroxide and hydrochloric acid that are reacted during the equation as well as implementing the stoichiometric equation to obtain the correct
number of moles. The heat lost by the two exothermic reactions can be determined by calculating the heat gained by the calorimeter. The exothermic reactions used
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 Spring '08
 Chiu
 Chemistry, Thermodynamics, pH, Calorimetry, Sodium hydroxide

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