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Analgesics in Excedrin

Performed by. James Forst, Sibora Peca Performed on 10/17/19, 10/24/19 Submitted on 10/31/19

Abstract Excedrin is a widely used pain reliever worldwide. Within in this experiment a separation was performed in order to determine the purity of each substance was separated from Excedrin and compared to the original substances. We began by separating each substance from a 1-gram sample, performing a melting point test with the dried separated product and using a TLC plate with samples of each substance as a control and then making an additional TLC plate as a basis of comparison. During the experiment values such as mass where taken. From a 1-gram sample, 0.09g of caffeine, 0.36g of acetaminophen and 0.07g of aspirin were observed. Due to the experiment a difference in purity was noted as the TLC plates of our substances were similar but not identical meaning purity was impacted by the original mixture. This will be analyzed based on the RF values which compare the distance travel by the component and the solvent. Based on theoretical yield calculations we expected 25% yield of Acetaminophen and Aspirin and around 6.5% Caffeine from a 1-gram sample containing 250mg of acetaminophen and aspirin and 65mg of caffeine. Objective This experiment demonstrated the effectiveness of separating substances from each other as well as providing a use for Thin Layer Chromatography. Thin layer chromatography was used to determine the effectiveness of the separation in the experiment as see if the purity of the separated substances differed from the original. Introduction Excedrin is a widely used pain reliever worldwide. It contains caffeine, acetopmetophen and aspirin. In a standard dose Excedrin contains 250mg of acetemetinophen 2500mg of aspirin and 65mg of caffeine. Within Excedrin Aspirin is used to reduce pain and inflammation by targeting specific substances within the body. Acetoemntophen acts in a similar fashion to aspirin. Caffeine is used as a stimulant for the central nervous system. The caffeine is believed to increase effectiveness of the other two drugs by improving blood flow and relaxing muscle contractions. This experiment begins by performing an extraction with a one-gram sample of Excedrin. Extraction is a method of separation used to remove or isolate a compound from another compound. To perform this separation ethanol will be used along with NaHCO3 and CHCl2. The first step is to take 15ml of warm CHCl2 and create a gravity filter. Place the filter over a beaker and place 1 gram of Excedrin and pour the 15ml of CHCl2 through the funnel. This will leave a filtrate and residue to be further separated. At this point the filtrate contains Aspirin and caffeine while the residue contains acetaminophen and a binding agent. This leaves two separate substances that will need to undergo further separation in order to end up with the 3 main components of Excedrin. Beginning with the filtrate, the filtrate will need to be moved into a seperatory funnel along with the addition of 2ml of NaHCO3. This will create an organic and aqueous layer that will give us the further separation of the original product. When these layers are separated into separate beakers the aqueous layer will need to have HCl added and then the solution will have to be dissolved cooled to room temperature then cooled in an ice bath which

will leave behind a crystallized aspirin product. The organic layer will need CaCl2 to be added along with heat until a dried prodcut remains. This dried product will be caffeine. With the residue we collected from the initial filtration 2ml of warmed ETOH will be added and filtered. In this case the remaining product within the filter is a binder used in Excedrin and within this experiment is solid waste. The filtrate after being heated and dried will give a product of acetaminophen. After separation of the 3 components of Excedrin we performed further experiments. We performed a Thin layer chromatography with sample of pure Excedrin, Aspirin, Acetaminophen and caffeine. We used this TLC plate as a reference to the TLC plate we would later create with our separated Excedrin, Aspirin and Acetaminophen. In addition to creating and analyzing TLC plates we performed melting point experiments with our dried samples and recorded the melting point in order to compare it with the expected boiling points of each substance to further determine purity of the separated substances. The melting points were observed using a Meltemp apparatus. By using the apparatus, we were able to see when our products melted opposed to their expected melting point. The TLC comparisons were we made were based on physical appearance observations. We noticed while our product was similar to the pure substance it was not identical despite using the same procedure to prepare the TLC plates. This most likely is indicating a purity difference. In addition to these observations we calculated the percent yield of products. The percent yield of the products is important in determining how much prodcut was recovered. Percent yield is the percent ratio of actual yield to the theoretical yield. It is calculated to be the experimental yield divided by theoretical yield multiplied by 100%. In our experiment it can be said that our solution is was oversaturated or super saturated as our final prodcut contained more mass then the original product we separated. Materials Material Filter Paper Funnel 125ml Seperatory Funnel Hot Plate 100ml Beakers Scale NaHCO3 CHCl2 CaCl2 Ethanol TLC plates Excedrin Aspirin Caffeine Acetaminophen UV light

Purpose To Separate Compounds Used to hold filter paper during separation To separate organic and aqueous layers Used for heating/Warming Used for compounds and products Used to weight materials Used for separation of products Used for separation of products Used for separation of products Used to aid in separation of compounds, TLC plate Used for Thin Plate Chromatography Control TLC plate, 1g for separation Control TLC plate Control TLC plate Control TLC plate Used for observation of TLC plate

Table of Physical Constants Compound

Apparatus

Name Caffeine

Melting Point (c ) 230-238.0

Molecular Weight (g) 194.11

Density 1.23g/ml

Acetaminophen

168.0

151.16

1.3g/cm3

Aspirin

135.0

180.16

1.4g/cm3

Ethanol

77.0

88.11

704kg/m3

Sodium Bicarbonate

109

83.98

2.1g/cm3

Methylene chloride

-96.8

84.93

13mg/ml

Calcium Chloride

782

110.98

0.745g/ml

Hydrochloric Acid

-114

36.46

82.3g/100g

Procedure and Observations Procedure 1. 1 gram of Excedrin was measured and prepared 2. 2ml of CH2Cl2 was gravity filtered with the Excedrin leaving a filtrate and residue 3. The filtrate is transferred to a seperatory funnel and 2ml of NaHCO3 is added. 4. The residue product is filtered with 2ml of warm ETOH 5. Filtration of residue leaves Acetaminophen as filtrate and binder is removed as solid waste. Final product is heated until dry. 6. The organic and aqueous layer was separated from the seperatory funnel 7. HCl is added to the aqueous layer and heated until it dissolved. It was then cooled to room temperature, then placed in an ice bath. 8. CoCl2 is added to the organic layer and decanted.

Observation 1.01g of Excedrin was used Some residue was left behind on the filter paper and funnel. Strong separation was observed through the formed layers. We used more than 2ml to rinse excess product. Product = 0.36g Acetaminophen We compared the weight of our product in a beaker when it was dried to the weight of the beaker when empty. Two 100ml beakers were used to carefully obtain each part. Product = 0.09g Caffeine We compared the weight of our product in a beaker when it was dried to the weight of the beaker when empty.

Product = 0.07g Aspirin We compared the weight of our product in a beaker when it was dried to the weight of the beaker when empty. 60.01 - 59.92 = 0.11 (Caffeine) 9. The final mass of each product was 33.30 - 32.94 = 0.36 (Acetaminophen) recorded by subtracting the container before and after the product was added 28.88 – 28.1 = 0.07 (Aspirin) 10. Ethanol is added to each product and a We added a small amount of ethanol to mix pipette is used to prepare a TLC plate with the remaining product. 11. A pencil is used to mark the TLC plate We had issues with a retractable pencil penetrating the plate. We switched to a wooden pencil 12. The TLC plate is set for 20 minutes in Our plate sat for approx. 10 minutes. We 2ml of ethanol contained in a 100 ml waited for the liquid to travel up 4 inches. beaker using the separated products 13. A TLC plate previously prepared We determined that our products may not be using pure compounds is compared as pure as original products but were similar. under a UV light

Flow Chart

Prepare 1g of Excedrin

Warm 15ml CH2Cl2 to filter Excedrin

Filter to leave filtrate and residuer

Add 2ml warm ETOH to Residue

Transfer filtrate to sepratory funnel, add 2ml NaHCO3

Filter residue, discard solid waste.

Filter and Seperate organic and aqueous layers

Add HCl to Aq layer and boil to dry prodcut

Place Aq layer in Ice bath

Calculate the mass of each product and subtract the weight of each appartus

Add COCl2 to Organic layer and dry product

Waste Disposal and Safety Precautions In terms of waste disposal and safety precautions in this experiment we used the proper lab wear. This lab wear includes closed toe shoes, a closed lab coat, eye wear, and rubber gloves. All of these lab wear items work together in order to protect the experimenter from the chemicals and apparatus they are working with. In terms of protection eye wear is the most important as many chemicals can irritate or damage the eyes. Gloves protect the experimenter from hot surfaces and direct skin reactions from chemicals. The lab coat and closed toe shoes protect experimenters from spills and damaging their clothes. Waste disposal is almost as important as the experiment itself. Not only is proper waste disposal safer as it prevents reactions and environmental damage it helps to prevent lab accidents. In our experiment all items went into their appropriate bins solids with solids, liquids with liquids and non-reactive chemicals went down the drain or into a marked trash bin. Results and Discussion Based on our separation procedure and results we yielded 0.09g of caffeine, 0.36g of acetaminophen and 0.07g of Aspirin from a 1g sample of Excedrin. Before recording the mass of

each product we calculated the weight of the beakers we used to hold them. This weight was then subtracted by the weight we recorded with our final products. In a standard dose Excedrin contains 250mg of acetaminophen 250mg of aspirin and 65mg of caffeine. Based on theoretical yield calculations we expected 25% yield of Acetaminophen and Aspirin and around 6.5% yield of Caffeine from a 1-gram. Based on our yield and calculating percent yield where the number we calculated as our theoretical yield was used. The equation used is as follows, actual yield/theoretical yield x 100. For caffeine we yielded 0.0009kg/0.065kg x 100 = 1.32% caffeine. For aspirin we yielded 0.0007kg/0.25kg x 100= 0.28%. and for Acetaminophen we calculated 0.0036/0.25x100=1.44%. Based on this our final products were lower than we initially expected as we ended up with less mass then our original separated product. We started with one gram then yielded 0.09g of caffeine, 0.36g of acetaminophen and 0.07g of Aspirin. Based on our calculations we determined our yield to be lower than our expected theoretical yield this may be due to purity difference and our experimental procedure. We would need to verify the exact theoretical percentages if the experiment were to be repeated. In another test of purity, we used TLC sheets. TLC sheets are effective for analyzing the purity and differences in our substance. We used the same procedure to prep each of our TLC plates to reduce experimental error. Each plate was left in ethanol for 20 minutes. We calculated RF values based on observation of the TLC plates under a UV light by taking measurements of each component in centimeters. Based on observation the pure plate was clearly different in terms of spotting then the separated plate. However, they experience the same spotting pattern overall. This difference in spotting can be attributed to concentration and purity of the samples. To determine an RF value we must measure the distance traveled by our tested component and divide it by the distance travelled by our solvent. A comparison of RF values is represented in the figure below.

RF value Comparison between Pure TLC plate and Seperated Compund TLC plate 1.000 0.900 0.800

RF-value (Y)

0.700 0.600 0.500 0.400 0.300 0.200 0.100 0.000 0.5

1

1.5

2

2.5

(X)

3

3.5 RF-Pure

4

RF-Seperated

4.5

Figure 1

Figure 2

Conclusion To conclude based on our separation of Excedrin we were able to separate and extract the 3 Analgesics properties of Excedrin. By process of extraction and separation we successfully yielded 3 products that represent the three properties of Excedrin. Based on further testing such as percent yield, theoretical yield, melting point and TLC plate analysis we were able conclude we isolated products however the purity of each is questionable. Based on theoretical yield and actual percent yield our products were determined to only contain a small percentage of each component. For caffeine we yielded 0.00011kg/0.065kg x 100 = 3.4% caffeine. For aspirin we yielded 0.0021kg/0.25kg x 100= .884%. and for Acetaminophen we calculated 0.0586/0.25x100=2.35%.Based on our TLC plates based on visual comparison they were similar however the solvent traveled differently on the pure then on the extracted compound plate. This once more can be due to purity and quality of our yielded products opposed to the controls we used in our experiment. TLC plates work based on difference in polarity. We calculated RF values and assigned our data to a graph in figure 1. In the figure 2 is our traced TLC plates. This figure represents the similarity in structure between our tests. The differences can be attributed to purity and quality of separated compounds and their original compounds. Overall all of the procedures used in this laboratory experiment put in to practice important procedures for separation, purification, calculating yields and drawing conclusions based on data. Our RF values between the pure and separated compounds also provides evidence for a successful separation as the numbers are consistent. Based on data we produced a successful separation despite quality concerns.

References I.

Williamson, Kenneth L. Organic Experiments. Vol. 9, Cengage Learning, 2011.

II.

Morrison, Robert Thornton., et al. Organic Chemistry. Pearson, 2011....