The mass of acetic anhydride is then divided by its molar mass to determine the number of moles of the solution we have: 8. Does this percent purity compare well with the results of the melting temperature test? Place the flask and its contents in a boiling water bath and stir untill all the solid dissolves. By replacing the arbitrary large amount of substance that was on the balance at first, it is then possible to view the total amount of substance removed from the large arbitrary amount and is, consequentially, in the desired receptacle. How to Make Aspirin — Acetylsalicylic Acid. The report progresses further giving details to the procedure carried out and the experimental technique that has been developed to show how aspirin is produced. The water that was used may not have been chilled enough and product was lost.
This soon became the pain killer of choice for physicians around the globe. During the synthesis, the H+ ions, given off by the catalyst, are being recycled. The mole ratio is 1:1 between salicylic acid and acetic anhydride in this reaction. These independent variables are the amounts of Salicylic acid, Acetic Anhydride, water and any other substances used in the experiment, the temperature of the water used in the experiment, the time spent performing certain tasks, and any other variable that is controlled by the user. Leave the filtered crystals undisturbed in the filter crucible for 10 minutes with the water aspirator on. Therefore when heating, heat was constantly being imputed into the system. For example, in water, the solubility of aspirin increases as temperature increases.
After the 15 minutes are done, use the filter crucible, water aspirator, and plastic filter flask to isolate the Aspirin crystals from the liquid. This curve, whether the liquid in the middle is higher or lower than the outside, is called the meniscus. After this vacuuming, spread out the Aspirin evenly on a labeled watch glass and put it in the oven for 30 minutes. Experimental Plan: An experiment will take place producing aspirin Acetylsalicylic acid from Salicylic acid and acetic anhydride. A precipitate began to form in the solution, and the solution in the Erlenmeyer flask was placed in a cold water bath for 5 minutes to complete the formation of aspirin crystals.
Based on the two reactions of aspirin synthesis shown below, methyl salicylate and benzene share a common intermediate which is salicylic acid: In order to prepare salicylic acid from wintergreen oil, an organic synthesis must be carried out. It is recommended for arthritis and related arthritic conditions, myocardial infarction prophylaxis. Aim: To prepare aspirin from salicylic acid. Data and Observations Figure 4 Object Mass g Initial Mass of Salicylic Acid 2. Variables: Independent and controlled variables: The amount of sulfuric acid used for catalysis and the amount of salicylic acid and acetic anhydride. In 1897, Felix Hoffmann discovered that there was indeed a way to make this drug less irritating to the throat and stomach: by reacting Salicylic acid with Acetic Anhydride, it would be possible to acetylate the Salicylic acid to remove one of these proton-donating groups and thus make it less irritating to the body.
Gloves were used to ensure chemicals did not come in contact with the skin as chemicals could enter the body through broken skin. To use this apparatus, one must use a small glass capillary tube to scoop up a small amount of the substance and then place this capillary tube inside the apparatus. The factors that contributed to the inaccuracy of the experiment are the following: Reflux: The apparatus used in the experiment were quite old. Due to the time factor it was unable to make this judgment. Using the of aspirin, you get the number of moles of aspirin produced. Fume cupboards were also used to ensure any dangerous vapour was not inhaled and also to keep the apprentice at a safe distance in case any vigorous reactions took place.
What is the solubility of Aspirin in water? Combining this with the number of grams per tablet will give the number of grams of aspirin. If no crystals form, gently scratch the sides of the flask with the stirring rod. 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. Because of the relatively small amount of product, small losses in product caused by the many transfers of material are greatly magnified in the percent yield. Procedure of the synthesis of aspirin: 3. As the report progresses the answers to the hypothesis become clear.
Another chemical concept used in this lab is that of a catalyst. Set up a Buchner funnel as described by your instructor, or in a manner performed previously. Place the test tube in the melting point apparatus checker. Generally take more care with the experiment. The advantage of using acetic anhydride is that you do not produce water which can be used for hydrolysis of the newly formed ester. For example the reflux used in the experiment has some sort of residue contained inside it.
The same observation was made in trial 2. Purity test 1 — 0. This reduced the strength of the acid and made the aspirin easier to ingest. The method described before is that followed by most manufacturers to make this chemical. Recrystallize from boiling water along with small quantities of spirit.
Hippocrates, the father of modern medicine lived sometime between 460 B. The same observation was made in trial 2. As soon as this occurs note the temperature. Place the flask in a beaker of warm water for ~15 minutes. Obtain acetic anhydride that you need for your reaction in your 10 mL graduated cylinder. The theoretical yield for trial 2 was found using the same method.