The first factor that caused a low percent yield was caused because we lost some crude product when we were moving our crude product from the weigh boat to the 25 mL Erlenmeyer flask. This lab facilitated an in depth look at both acid-catalyzed and base-catalyzed reactions to produce aspirin from salicylic acid and the critical differences between the two. In addition to irritation caused by acidity, aspirin causes stomach irritation by inhibiting the production of prostaglandins, hormones responsible for slowing gastric acid production. The percentage yield was calculated as 44. Another is measuring the melting point of the aspirin sample, which will in turn indicate the purity of the sample.
Due to this, now carbon has a positive charge which will attract the lone pairs of oxygen creating a double bond, yet again, creating positive charge on oxygen. This showed distinct differences in the two substances but similarities were also apparent showing aspirin, in some level, was created. There are reports that American Indians, before the time of Columbus, used special teas made from the bark of willow trees to reduce fever. Abstract: The goal of this experiment was to synthesize aspirin. This method of forming acetylsalicylic acid is an esterification reaction.
After adding the acetic acid anhydride and the sulfuric acid into the flask, the. After cooling for an additional 5 minutes, pour the contents in the 125mL Erlenmeyer flask into a Buchner funnel attached to the vacuum filtration apparatus. Historically, its first account was by a Greek physician called Hippocrates when he recorded the effects of the powder created from the willow tree at curing childbirth and fever. Although aspirin is not soluble in water, everything has some solubility in water and in this case aspirin is soluble in higher temperatures and large amounts of water. Obtain mass of dry salicylic acid. One can reduce the number of transfers by forgoing the step involving the mortar and pestle: though the product will not be a fine and powdery as it could otherwise be, much of the rinsed product is wasted in both the transferred and the act of pulverizing the product as well.
Application of sample - capillary open on both ends is used to spot the solution of each sample 2. For the sake of time and efficiency, sulfuric acid was added as a catalyst to speed up the reaction. Aspirin StructurePhenol Structure 2- Hydroxybenzoic Willow Bark Synthesis Acid structure Chemical tests 1. It is additionally possible that we over-titrated when back-titrating, as there is no color to indicate the difference between an acidic solution and a neutral one. Other variables that could lead to the yield being less than 100% are: transfer of the product between containers, an incomplete reaction could have occurred, and is likely to have, where each compound does not fully react when it should due to factors beyond control, this will lower the products final mass. If the experiment went as expected, a pure sample of aspirin with a high percent yield would have been obtained.
One notable source of error is the amount of product wasted in transfers from one piece of equipment to another. Can you see what effect this had on the end product? Then, it is released into the blood stream and has pain-relieving effects How much of the reagents should you use? Conclusion The overall objectives were to synthesise aspirin from 2-hydroxybenzoic acid and willow bark, and qualitatively determine the purity of each product, this was achieved as aspirin was produced from both the willow bark and the substances. These are separate from dependent variables, whose name is derived from the fact that these variables depend on the independent variables. Both salicylic acid and aspirin are not very polar. Jeana Greaves Chem3301-112 June 19, 2013 Synthesis of Aspirin from Methyl Salicylate Introduction The synthesis of Aspirin Acetyl Salicyclic Acid began with methyl salicylate and sodium hydroxide as the reagent. To conclude if all variables and experimenter error was controlled a purer product would have been made and a higher yield would have been produced.
To measure an amount of a liquid, the liquid to be measured is poured into the graduated cylinder. Next a melting point test was performed on the purified aspirin product. As a result, if we were to improve this experiment, we would use an indicator such as bromthymol in all titrations that has a specific color for a neutral solution to increase the accuracy of the titrations. The common chemical name is acetylsalicylic acid. Vacuum filtration can be used to help dry out a sample as well.
After cooling in an ice bath which further facilitates recrystallization and purification , the mixture was then suction filtered. Ibuprofen is sold under the brand name Advil and Acetaminophen is sold under the brand name Tylenol. Another chemical concept used in this lab is that of a catalyst. Why is it not necessary to measure the volume of acetic anhydride to two significant figures? Any vapours that are given off are cooled back to the liquid by the condenser and fall back into the reaction vessel. As such, any reactant that exists in an amount more than this whole number ratio is known as an excess reactant and some will be left over when the reaction is completely finished.
The resulting percentage yield is 65. The water that was used may not have been chilled enough and product was lost. Once again, the electrophilic oxygen takes the lone pairs between the O-H bonds to form the final product of Aspirin and acetic acid. The true melting point of acetylsalicylic acid is 135° C, therefore our percent error range of for the boiling point is found to be 2. In Table 8, the differentiation of synthesized acetylsalicylic acid from commercially available aspirin was accounted for.
Cold water was used to minimize dissolving the product. With a name, Bayer proceeded to commercialize the Acetylsalicylic Acid in 1899, though it was not until 1915 that Aspirin was released as an over-the-counter non-steroidal anti-inflammatory drug. The bottle was filled with distilled water to the seam near the top of the bottle. Small amounts of sulfuric acid and occasionally phosphoric acid are almost always used as a catalyst. Boil water on the hot plate and dissolve aspirin using a minimum amount of boiling solvent until all of the aspirin is completely dissolved homogeneous solution. The crystal product will be stuck at the top of the capillary tube. .
The crucible is placed in the aspirator with a rubber stopper between the two pieces of equipment to ensure the seal between them. We use it for migraine, prevention of heart attacks, diabetes, and to reduce. Transfer 90% of salicylic acid into a 50 mL Erlenmeyer flask 3. The flask was placed into the 70°C water bath and heated for 10 minutes. Therefore, to obtain the purity by percent, the following equation can be used.