Formal Lab Report for Extraction lab PDF

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Formal lab report for extraction lab! Reviewed by both the writing center as well as a highly skilled tutor!...

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321Ahmad Rafay 10/03/2018 Title: Separation of the Constituents of an Analgesic Preparation: Acid/Base Extraction Date Performed: 09/24/2018 Objective/Purpose: Compounds/mixtures today, in the world of different medicines, extraction a method to use when different components by solubility in order to obtain a more pure substance. The objective of the experiment was to perform and learn how to separate the individual components (aspirin & sucrose) within a special analgesic product called Phensuprin at VCU. We also determined their melting points to be able to calculate the amount of each. The theory of extraction is used when one solute is more soluble in one solvent than the other and is conceptualized in this lab. Structures, Hazards and Physical Properties (Products/Reactants): Structures 1)

Acetylsalicylic Acid or Aspirin

3)

Acetanilide

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2) Hydrochloric

4) Dichloromethane

1

4)

Sodium Bicarbonate

5) Water

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6) Sucrose

Chemical Hazards: 1) Dichloromethane: Carcinogen, Toxic, Irritant 2) Acetylsalicylic Acid: Irritant, Poison 3) Acetanilide: Toxic, Irritant 4) Hydrochloric Acid: Poison, Corrosive Irritant, toxic if inhaled Physical Properties: 1) Hydrochloric Acid Molecular Weight: 36.458 g/mol Melting Point: -114.22 Degrees Celsius Boiling Point: -85.05 Degrees Celsius Density: 1.19 g/ml 1 1.

Structures taken from http://www.sigmaaldrich.com/united-states.html

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Physical properties taken from http://www.sigmaaldrich.com/united-states.html

Solubility: in methanol, ethanol, and ether 2) Acetanilide Molecular Weight: 135.166 g/mol Melting Point: 114.3 Degrees Celsius Boiling Point: 304 Degrees Celsius Density: 1.219 g/cm^3 Solubility: in water 3) Aspirin Molecular Weight: 180.159 g/mol Melting Point: 135 Degrees Celsius Boiling Point: 140 Degrees Celsius Density: 1.4 g/cm^3 4) Dichloromethane Molecular Weight: 84.927 g/mol Melting Point: -95 Degrees Celsius Boiling Point: 39.75 Degrees Celsius Density: 1.3255 g/cm^3 Solubility: in organic solvents 5) Sodium Bicarbonate Molecular Weight: 84.01 g/mol Melting Point: 50 Degrees Celsius Boiling Point: 851 Degrees Celsius Solubility: in water

6) Water (H2o) Molecular Weight: 18.015 g/mol Boiling Point: 100 Degrees Celsius Density: 1 g/cm3 Solubility: in water

Procedure of Extraction lab After weighing 2 g of the Phensuprin sample into a 125 mL, 50 mL of dichloromethane was added and stirred into the mixture until all solid dissolved. Filter paper was weighed and fluted and the mixture was filtered through the filter paper by gravity filtration after weighing it. After the filter paper and sucrose were completely dry, the filter paper plus solid was weighed and amount of sucrose recovered was calculated. The result was reported as a weight and percent of the total weight of Phensuprin (percent composition). Acetylsalicylic acid was isolated from adding filtrate to a funnel. Two 25 mL portions of 5% sodium bicarbonate solution were extracted. To do this, one portion of sodium bicarbonate solution was added to the separatory funnel containing the dichloromethane solution. The separatory funnel was shaken for 1-2 minutes by carefully placing our finger on the top. Pressure was released from the funnel every few seconds. After the extraction period finished, pressure was released and the funnel was placed in a ring/clamp. The stopper was removed, layers separated, and lower dichloromethane layer drained into a 125 mL Erlenmeyer flask. The aqueous layer from the funnel was poured into a 400 mL beaker. The dichloromethane layer was returned to the funnel and the same procedure was repeated with the second portion of sodium bicarbonate solution. The two aqueous layers were combined and the dichloromethane layer, saved. The two combined layers

were placed in an ice bath and slowly a concentrated hydrochloric acid of 10 mL was transferred. Foaming occured as the beaker was swirled between every HCl addition. After completing the addition, the pH was tested of the solution by inserting a glass rod and touching the solution at the tip of the glass rod with a pH paper. Depending on the pH value, small amounts of concentrated hydrochloric acid was added to lower the pH to 2 or below. Aqueous solution was cooled in the ice bath until a solid of acetylsalicylic acid formed. The solid washed with 5 mL of cold water after being collected with vacuum filtration. After filtration was complete to help dry the solid, it was transferred to an uncapped sample. The solid was then weighed and the amount of acetylsalicylic acid recovered was calculated and again, reported as a weight and percent of the total Phensuprin (percent composition). The remaining organic solution over anhydrous sodium sulfate. Afterwards, a scoop of the anhydrous sodium sulfate was placed into the “wet” methylene chloride solution and swirled until the agent became hydrated until some of the drying agent remained free flowing. After swirling for several minutes, the agent was filtered through fluted filter paper into a pre-weighed 100 mL round-bottom flask. Using a rotary evaporator the methylene chloride was completely evaporated. The Acetanilide solid was saved and after all three solids dried, the amount recovered of each was calculated. The result was in percent composition and the melting point of each was taken. Percent Composition and Calculations: ● Acetylsalicylic acid mass = 0.93 g ● The mass of Acetylsalicylic acid/mass of Phensuprin) x 100 = The Percent Composition (0.93 g acetylsalicylic acid/2.00 g Phensuprin) x 100 = 47% ● (Weight of acetanilide with flask) – (weight of flask) = Mass of acetanilide 41.976 g – 41.59 g = 0.386 g acetanilide

● (The mass of Acetanilide/mass of Phensuprin) x 100 = The Percent Composition (0.386 g acetanilide/2.00 g Phensuprin) x 100 = 19.3% ● (Weight of sucrose and filter paper) – ( weight of filter paper) = Mass of sucrose 1.689 g – 1.03 g = 0.659 g sucrose ● (The mass of sucrose/mass of Phensuprin) x 100 = The Percent Composition (0.659 g sucrose/2.00 g Phensuprin) x 100 = 32.95%

Percent Recovery = [(mass of sucrose = mass of acetanilide = mass of acetylsalicylic acid) / mass of Phensuprin] x 100 [(0.659 g sucrose + 0.386 g acetanilide + 0.93 g acetylsalicylic acid)/2.00 g Phensuprin] x 100 = 98.75% Results: The results concluded the calculated masses of all three components to be 0.93 g of acetylsalicylic acid, 0.659 g sucrose, and 0.386 acetanilide. In Phensuprin, the percent composition values were of 49% acetylsalicylic acid, 19.3% acetanilide, and 32.95% sucrose. All the masses result in a percent recovery of 98.75%. The melting points that were used to test the purity of aspirin, sucrose, and acetanilide ranged between 128.6°C – 131.6°C, 150.2°C – 165.0°C, and 97.7°C-103.6°C, respectively. For the literature melting points, the values were 135 degrees celsius, 186 degrees celsius, and 114.3 degrees celsius. Discussion In this experiment, the method of extraction was used; in which Phensuprin was separated into its three components of sucrose, acetanilide, and acetylsalicylic acid. The Phensuprin was a VCU analgesic that after separated, was more easily able to be analyzed. All 3

components were obtained successfully without any evaporation taking place. Through the use of the separatory funnel, extraction was made possible in a more efficient way. After placing acetanilide acid, it was isolated through its level of acidity. An acid-base reaction occurred after adding sodium bicarbonate which left dichloromethane to be drained from the lower layer. An upper aqueous layer also formed. This acid-base reaction was advantageous to the experiment because it formed a water soluble salt and water which was sent to the top because of density levels. This helped extract the sucrose and acetylsalicylic acid. In the extraction of acetanilide a rotary evaporator was used to form the solid by the evaporation of dichloromethane. This was because of the lack of acidity levels which does not allow a practical reaction between it and sucrose as well, unlike acetylsalicylic acid. After these extractions a percent composition of 98.75% was calculated from all 3. The missing 1.25% could possible not have been obtained due to several different errors. During filtration, components were able to be lost as well as when extracting using a separatory funnel. Because the ranges of the melting points were slightly lower than the literature values by a couple degrees celsius, there could be an indication that due to impurities in our substance, an improper percent recovery was obtained. References Acetylsalicylic Acid; MSDS No. A5376 [Online]; Sigma-Aldrich: Saint Louis, MO, January 2, 2015, http://www.sigmaaldrich.com/html (October 7, 2018) Acetanilide; MSDS No. 397327 [Online]; Sigma-Aldrich: Saint Louis, MO, June 27, 2014, http://www.sigmaaldrich.com/html (O

Sucrose; MSDS No. S7903 [Online]; Sigma-Aldrich: Saint Louis, MO August 13, 2014, http://www.sigmaaldrich.com/html (October 7, 2018). Dichloromethane; MSDS No. 270997 [Online]; Sigma-Aldrich: Saint Louis, MO, November 24, 2014, http://www.sigmaaldrich.com/html (October 7, 2018)

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Physical properties taken from http://www.sigmaaldrich.com/united-states.html...