First of all, I would like to thank our Almighty God for giving all the needs and also the knowledge, without You all of this would not be possible. To madam Jeandalyn Celis, thank you even though we are not prepared entering the class, you give the recap of the previous experiment that is conducted. Even though we are too noisy inside the class, your temperance is still there for us. And most of all we thank your great consideration in all things. To our co-partner in this experiment, Mikkha Deligero and Nhelsar Mel Sarmiento, for giving your full support and helping us to finish the experiment.
To the chemistry stockroom and their stuff, for giving all our needs for the experiment. J. P. M and E. A. M ABSTRACT This experiment is conducted to know how to prepare an aspirin. Aspirin is a salicylate. It works by reducing substances in the body that cause pain, fever, and inflammation. Salicylic acid and acetic anhydride were used in the said experiment. 2 grams of salicylic acid and 4mL of acetic anhydride were mixed together and were added by 5 drops of phosphoric acid that serves as the catalyst. Through heating and filtering, aspirin crystals were form and produced.
For 2 grams of salicylic acid, there should be 2. 61 grams of aspirin that will be produced. Only 2. 57 grams of aspirin were produced because of some factors like unscrape aspirin inside the flask and left over aspirin in the filter paper. The percentage yield results to 98. 47%. INTRODUCTION Aspirin is a salicylate drug, often used as an analgesic to relieve minor aches and pains, as an antipyretic to reduce fever, and as an anti-inflammatory medication. The active ingredient of Aspirin was first discovered from the bark of the willow tree in 1763 by Edward.
Stone of Wadham College, Oxford University. He had discovered salicylic acid, the active metabolite of aspirin. [1] Aspirin was first synthesized by Felix Hoffmann, a chemist with the German company Bayer in 1897. [2] Salicylic acid, the main metabolite of aspirin, is an integral part of human and animal metabolism. [3] Aspirin also has an antiplatelet effect by inhibiting the production of thromboxane, which under normal circumstances binds platelet molecules together to create a patch over damaged walls of blood vessels.
The main undesirable side effects of aspirin taken by mouth are gastrointestinal ulcers, stomach bleeding, and tinnitus, especially in higher doses. In children and adolescents, aspirin is no longer indicated to control flu-like symptoms or the symptoms of chickenpox or other viral illnesses, because of the risk of Reye’s syndrome. [4] Aspirin is part of a group of medications called nonsteroidal anti-inflammatory drugs (NSAIDs), but differs from most other NSAIDs in the mechanism of action. Today, aspirin is one of the most widely used medications in the world, with an estimated 40,000 tons of it being consumed each year. [5]
In countries where Aspirin is a registered trademark owned by Bayer, the generic term is acetylsalicylic acid (ASA). [6] Acetylsalicylic acid (ASA) decomposes rapidly in solutions of ammonium acetate or of the acetates, carbonates, citrates or hydroxides of the alkali metals. ASA is stable in dry air, but gradually hydrolyses in contact with moisture to acetic and salicylic acids. In solution with alkalis, the hydrolysis proceeds rapidly and the clear solutions formed may consist entirely of acetate and salicylate. [7] EXPERIMENTAL.
Materials Salicylic acid Acetic anhydride Concentrated phosphoric acid Ice Cold deionized water Erlenmeyer flask Balance Buchner funnel Thermometer B. Methodology Preparation of mixture Two grams of salicylic acid was added in a 50ml Erlenmeyer flask. Then 4ml of acetic anhydride was poured into the flask to be down any crystals of salicylic acid to the walls of the container. 5 drops of concentrated phosphoric acid was added in the flask to speeds up the reaction. Heating the mixture The flask was clamped in a beaker of water supported by wire gauze, then the water was heated about 75C for about 15minutes while stirring the mixture in the flask occasionally.
Creating the crystals As the vapors stopped releasing, the flask was removed from the water bath and 19ml of water were added in the flask. The mixture was cooled and the crystals of aspirin appeared and flask was put on an ice bath to hasten the crystallization. Collecting the crystals The aspirin was filtered through the Buchner funnel, using suction. When the liquid was drained, 5ml of ice cold deionized water was poured of the crystals, then the washing step was repeated with a second 5ml of ice cold deionized water.
The filtered aspirin was transferred into a clean watch glass that has been preweighed to the nearest 0. 01grams. RESULTS AND DISCUSSION The result of the experiment will be showed below and discuss as well. From the experiment that was conducted, the theoretical yield of aspirin in grams is 2. 61 grams and the actual yield of aspirin (amount of aspirin that was collect through the experiment) is 2. 57 grams. The percent yield has a result of 98. 47%.
Based on actual mass of salicylic acid that was used in the experiment, theoretical yield of aspirin in grams were calculated by the equation below, Theoretical yield= Mass of salicylic acid used x molecular weight of aspirin molecular weight of salicylic acid Were the molecular mass of aspirin is 180, and the molecular mass of salicylic acid is 130. Percentage yield= actual yield theoretical yield x100 Where actual yields means the number of grams of product actually obtained.
Theoretical yield= 2. 0 grams of salicylic acid x 180 grams permole of aspirin 138 grams per mole of salicylic acid =2. 61 grams of aspirin Percentage yield= 2. 57 grams of aspirin 2. 61 grams of aspirin x100 =98. 47% From the 2. 0 grams of salicylic acid, there should be an exact amount (in grams) of aspirin that is 2.
61 grams. That amount is derived from the formula of theoretical yield. Based on the experiment, the 2. 57 grams of aspirin that were collected was divided to 2. 61 that is the theoretical yield and multiplied to 100%. The result is 98. 47% for the percentage yield. 100% is not reached because of not all of the aspirin crystals were scrape from the flask. When filtering the aspirin crystals, some of it went to the walls of Buchner funnel. When transferring the aspirin in the filter paper to the watch glass, some of the crystals were remain on the paper.
CONCLUSION
In this experiment, the theoretical yield (true value) is 2. 61 grams of aspirin. The actual yield (experimental value) is 2. 57 grams of aspirin which is closer to the true value. Only 0. 04 grams of aspirin were not collected due to some errors. The percentage yield is 98. 47% which presents the actual yield over theoretical yield.
RECOMMENDATION In order refrain from errors, remember to be patient and don’t rush the experimentation because it might result for nothing and the experiment will most likely to fail, always make an accurate measurement in all of the process.
This also may occur errors, including computations.
REFERENCE 1. Stone E (1763). “An Account of the Success of the Bark of the Willow in the Cure of Agues. In a Letter to the Right Honourable George Earl of Macclesfield, President of R. S. from the Rev. Mr. Edmund Stone, of Chipping-Norton in Oxfordshire”. Philosophical Transactions (1683–1775) 2. Sneader, W. (2000). “The discovery of aspirin: A reappraisal”. BMJ (Clinical research ed. ) 3. Paterson, J. R. ; Baxter, G. ; Dreyer, J. S. ; Halket, J. M. ;
Flynn, R. ; Lawrence, J. R. (2008). “Salicylic Acid sans Aspirin in Animals and Man: Persistence in Fasting and Biosynthesis from Benzoic Acid”. Journal of Agricultural and Food Chemistry. 4. Macdonald S (2002). “Aspirin use to be banned in under 16-year olds” 5. Warner, T. D. ; Warner TD, Mitchell JA (2002). “Cyclooxygenase-3 (COX-3): filling in the gaps toward a COX continuum? “.
Proceedings of the National Academy of Sciences of the United States of America 6. The use of aspirin”. Wordconstructions. com. Retrieved 11 May 2011 7. EF Reynolds, ed. (1982). “Aspirin and similar analgesic and anti-inflammatory agents”. Martindale: The Extra Pharmacopoeia (28th ed. ). pp. 234–82.