Beer’s Law And Calorimetry

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You will write background,purpose, procedure, and a conclusion on Beer’s Law. This will be double spaced as well.

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Experiment Beer’s Law & Colo rimetry
Beer’s Law & Colorimetry
Angela Carraway, Ph.D. and Peter Jeschofnig, Ph.D.
Version 42-0140-00-01
Lab Report Assistant
This document is not meant to be a substitute for a formal laboratory report. The Lab Report
Assistant is simply a summary of the experiment’s questions, diagrams if needed, and data tables
that should be addressed in a formal lab report. The intent is to facilitate students’ writing of lab
reports by providing this information in an editable file which can be sent to an instructor.
Exercise 1
QUESTIONS FROM PROCEDURES
1. Convert %T to absorbance and prepare a Beer’s Law plot using this data.
Concentration of Various Samples
Sample Identification
Code
Concentration of M
(mol/L) %T A = 2 – log(%T)
Q5000 4.00 x 10-4 17.9
Q5001 3.20 x 10-4 25.0
Q5002 2.40 x 10-4 35.7
Q5003 1.60 x 10-4 50.2
Q5004 8.000 x 10-5 70.8
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Experiment Beer’s Law & Colo rimetry
Concentration of M
Sample Identification
Code %T A = 2 – log(%T) A M
Q021015-01 43.7 0.35951856 0.36 0.000192
Q021015-02 44.1 0.35556141 0.36
Q021015-03 43.8 0.35852589 0.36
Q021015-04 44.1 0.35556141 0.36
Q021015-05 43.8 0.35852589 0.36
QUESTIONS FROM PROCEDURES
3. What is the concentration of M in these samples?
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Experiment Beer’s Law & Colo rimetry
4. What was their percent error?
5. Does Batch 021015 meet legal requirements?
Exercise 2
Observa tions
Data Table 1: Concentrations of Blue Dye
Well # 1 2 3 4 5 6 7 8 9 10
Drops of Blue Dye Solution 1 2 3 4 5 6 7 8 9 10
Drops of Distilled Water 9 8 7 6 5 4 3 2 1 0
Calculated Concentration
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Experiment Beer’s Law & Colo rimetry
Exercise 3
Observa tions
(Only if colorimeter is used in this experiment.)
Data Table 2: Dilution
Test tube
Number Solutions Concentration

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(M)
Concentration
(ppm)
3 Starting dilution (100 mL water and drops of
blue#1 dye)
2 1:1 Dilution (1 part water – 1 part starting dye
solution)
1 2:1 Dilution (2 parts water – 1 part starting dye
solution)
0 Zero standard – distilled water 0 0
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Experiment Beer’s Law & Colo rimetry
Data Table 3: Resistance vs. Concentration
Zero
standard
2:1
standard
1:1
standard
Original
dilution
Commercial
drink sample
Concentration (M) 0
Concentration (ppm)
Resistance, Ω
Resistance, Ω
Average Resistance, Ω
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Experiment Beer’s Law & Colo rimetry
Exercise 3
QUESTIONS
Fully discuss answers to the following questions. Yes or No responses are not sufficient.
A. Was your calibration curve as linear as you expected?
B. Did you experience any “drift” of the resistance readings?
C. What is the equation of your best-fit line?
D. What commercial drink did you analyze?
E. Assuming that the same commercial drink was analyzed in both colorimetry methods, how
did the results compare?
F. Which technique should give more accurate results?
G. What are some of the potential sources for errors in this experiment
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