beer's law

Running head: Beer’s Law And Calorimetry

Beer’s Law And Calorimetry

Adriane Bellard

Ocean County College

Beer’s Law is also referred to as the Beer- Lambert law or the Bouguer- Beer Law. The principle is based on an electromagnetic radiation that is passed through a sample, wavelength is detected by the sample. As a result strength of transmitted light is gradually reduced. The measurement of the reduced strength of radiation is supported by the spectrophotometer. Based on Beer’s Law the strength of incident light is comparative to the length of thickness of the absorbing medium and the concentration of the mixture. The principle of calorimetry is the discipline or act of calculating changes in limits of chemical reactions, physical changes, and phase transitions for the intention descending the heat or heat transfer connected to those changes.

The purpose of the experiment is to determine the concentration of an unknown using Beer’s Law, also to determine the concentration of blue dye #1 using visual colorimetry and the concentration of blue dye #1 using a simple colorimetry. At last define electrochemical radiation, spectroscopy in relation to Beer’s Law.

Procedure I

A spectrometer is essential to attain the data from absorbance studies, you will not collect the data yourself, as a substitute you will work with data that is already collected. Imagine you are working as a technician for a testing laboratory that has been hired by company Q. Your job is to objectively test the quality of an over the counter drug made by Q. Q markets a product in which the effective ingredient,M, is combined with unused ingredients. Subsequently, you formulate a technique in which you test for the presence of active ingredients in inactive ingredients. Normally, this is done through some chemical reaction.

1. You obtain the following data:
2.
Table 1: Concentration Of Various Samples

Sample Identification Code:
Q5000
Q5001
Q5002
Q5003
Q5004
Q5005

Concentration Of M (mol/L)
4.00x10-4
3.20x10-4
2.40x10-4
1.60x10-4
8.000x10-5

%T
17.9=4000
25.0=102400
35.7=24000
50.2=16000
70.8=80,000
2.You begin to analyze the drug. You have five bottles of the drug from batch 021015. You analyze these samples and obtain the following data:

Table 2: Percent Transmission Of Various Samples

Sample Identification Code:

Q021015-01=43.7
Q021015-02=44.1
Q021015-03=43.8
Q021015-04=44.1
Q021015-05=43.8
What is the concentration of M in these samples? 4.00x10-4,17.9=035951856 0.36 0.000192
3.

3.20x10-4,25.0=0.35556141 0.36

2.40x10-4,35.7=0.35852589 0.36

1.60x10-4,50.2=0.35556141 0.36

8.000x10-5,70.8=0.35852589 0.36

1: 0.000192

2:0.000183

3:0.000173

4:0.000163

5:0.000153

4.The percent error would be 5%

5.No, the batch does not meet legal requirements

Data Table 1: Concentrations Of Blue Dye

Well Number 1 : 1,2,3,4,5,6,7,8,9,10

Drops 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: 9,8,7,6,5,4,3,2,1,0

Exercise 2: Purpose

In this experiment, the student will visually analyze the concentration of blue dye for qualitative results.

Procedure 2: 1. Before beginning set up a data table similar to data table 1 in the lab report assistant section.

2.Preparation of the standard:

A. Fill a beaker to the 100 ml mark with distilled water.

B. Add 20 drops (approximately 1.0ml) of blue #1 dye and stir. This will give you a starting

concentration of approximately 2.6x10-4 M. The color of commercial drinks may vary in

intensity. If a darker commercial drink is used for this experiment, more drops of blue #1

dye will have to be added to the starting solution to result in a slightly darker blue color

than the commercial drink to be used. To prepare a standard for the analysis of G 2

Gatorade (blueberry –pomegranate) only 5 drops of water. This produced a starting color that was darker than the sample to be analyzed and had a concentration of 6.5x10-5M

C. Calculate and record the concentration of this “starting” solution in your notebook.

D. Remember, the concentration of the commercial dye solution before dilution is 0.026 M.

E. Remember that we assumed 20 drops=1M1

F. Fill the 1-ml fine tip pipet with the diluted dye by squeezing the bulb, placing its tip in the

G. beaker’s solution, and releasing the bulb.

H. Place a 12 well strip on a white sheet of paper towel with the number 1 well on your left.

I. Using a good delivery technique and the 1-ml fine tip pipet of dye solution, fill 10 wells in

J. the 12 well strip per the following data table. For consistency in drop size, use the same fine

K. tip pipet to dispense both the dye and the water.

L. Seal the top of the strip with clear tape so that it cannot be accidently spilled. This is your

M. “standard” strip, keep it for the next part of the experiment.

N. Use the data table in your lab report to record calculations of molarity of blue dye.

O. Rinse the pipet by sucking and expelling water from it 6 to 8 times and then while pressing

P. the bulb, forcefully swinging it in a downward arch several times.

4. Determination of food dye concentration in a commercial sample:

*In the case of the kool-aid, mix the content of the package with 2 liters of water. * You may need to pour a small amount of your drink into a saucer so you can fill your 1-ml microtip pipet.

* To avoid diluting your product with any water remaining in your small drop pipet, rinse it with the commercial product by sucking in and expelling out product from the bulb 2 to 3 times. A. Fill your 1-ml fine tip pipet with the commercial drink product. Place 10 drops of it in only one well of a 12 well strip. Tape the top of the well to avoid spills.

B. Place the standard strip you made in part I on top of the product strip and hold them at eye level to

C. view both strips through their sides at the same time. Move the strips back and forth comparing

D. the amount of light absorbed by the product to the standards. Determine which standard well

E. best matches the product. If the intensity is between wells, estimate the concentration.

C. Refer to the matching standards position in the data table and record the approximate concentration of blue #1 dye in the product.

D. Occassionally a commercial product may be darker than the darkest blue in your standards strip. In that case you have to dilute the product. The first dilution should probably be 1:1 (i.e.,5 drops of product and 5 drops of water). If this dilution is still too dark try a 10 fold dilutioin (i.e.,1 drop of product and 9 drops of water).

F. After you match the diluted product with the standard strip remember to multiply by the dilution

G. factor to obtain the correct concentration.