CHEM 152 Experiment 4: Thermodynamics I (Calorimetry) (GRADED A)
176 views 0 purchase
Course
CHEM 152
Institution
University Of Washington
DATA AND CALCULATIONS
A: Heat Capacity of the Calorimeter
Run 1 Run 2 Run 3
Voltage, V (J/C) 2.2 2.2 2.2
Current, A (C/s) 2.24 2.28 2.25
Time (s)
Initial temperature, oC 25.7 26.4 26.7
Final temperature, oC 30.4 31.0 31.3
*Energy into calorimeter from power supply, (q), J
*Heat Capacity ...
chem 152 experiment 4 thermodynamics i calorimetry
Written for
University Of Washington
CHEM 152
All documents for this subject (1)
Seller
Follow
Examhack
Reviews received
Content preview
Chem 152 Experiment #4: Thermodynamics I (Calorimetry)
By signing below, you certify that you have not falsified data, that you have not plagiarized any part of this lab report, and that all Note:
calculations and responses other than the reporting of raw data are your own independent work. Failure to sign this declaration will All sections of
result in 5 points being deducted from your report score. this report must
be typed
Total Points = 60 pts (10 notebook, 50 report)
Signature:
Data Entry 2 pts
DATA AND CALCULATIONS
A: Heat Capacity of the Calorimeter
Run 1 Run 2 Run 3
Voltage, V (J/C) 2.2 2.2 2.2
Current, A (C/s) 2.24 2.28 2.25
Time (s) 420 410 420
o
Initial temperature, C 25.7 26.4 26.7
o
Final temperature, C 30.4 31.0 31.3
*Energy into calorimeter from power supply, (q), J 2070 2060 2080
o
*Heat Capacity of Calorimeter, Ccal, J/ C 440 447 452
o
Average, Ccal 446 J/ C
o
Standard Dev 5.81 J/ C
*Type an example of the calculations you are performing for q and Ccal. (3 pts)
q = current * voltage * time = 2.24 C/s * 2.2 J/C * 420 s = 2069.76 J ≈ 2070 J
= q / T = 2069.76
CcalEnthalpy o
J / (30.4ofCWater o o
- 25.7 C) = 440.374 J/ C ≈ 440 J/ C o Help with Formulas in Excel
B: of Fusion
In Excel type "=average(range of values)" but
Run 1 Run 2 instead of entering a range, just click at one end
Ccal(Average), J/ C
o of the values and drag mouse to the other end.
446 446
Mass of calorimeter, stir bar and water, For standard deviation, in Excel type
g 113 113 "=stdev(range of values)".
Mass of calorimeter, stir bar, and water
+ mass of added ice (or melted ice), g
115 115
Mass of ice, g 2.52 2.68
Temperature of calorimeter before ice
addition, oC 26.4 26.3 *Type examples of the calculations you perform for the following:
Temperature of ice before addition to (a) q cal (2 pts)
the calorimeter, oC 0.0 0.0 (b) q for heating the water that was ice (warming melted ice) (2 pts)
Temp. of the calorimeter after addition (c) Hfusion (melting the ice) (2 pts)
and melting of the ice, oC 23.4 23.0
Tcal -3.00 -3.30
-qcal = -CcalT = -446.469 J/oC * -3oC = 1339.407 J ≈ 1340 J
* (a) Heat lost by calorimeter (q cal in J) -1,340 -1,470
water from ice 23.4 23.0 qcal = -1340 J
Specific heat of water, J/g.oC 4.18 4.18 qwater that was ice = 4.184 J/goC * 2.52 g * 23.4oC = 246.722 J ≈ 247 J
Heat gained by ice cube to warm water
* (b) from ice temperature (q in J)
247 258 H
fusion = (1339.407 J - 246.722 J) / 2.52 g = 433.605 J/g ≈ 434 J/g
*(c) Enthalpy of fusion of ice, H fusion in J/g 434 453
Average H 443 J/g
Standard Dev 13.4 J/g
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Examhack. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $9.49. You're not tied to anything after your purchase.
