Hypothesis Of Synthesis Of Aspirin

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Formal Report Laboratory Skills in Inorganic and Organic Chemistry Aim The aim of this experiment is to synthesise aspirin through esterification and how to purify it using the recrystallization method. It is also to distinguish aspirin by determining the melting point. Hypothesis of the characterized aspirin: The aspirin should be white and shiny in appearance and it should have a melting point of estimated 139degrees celcius. Introduction Aspirin is one of the most common drugs that does not require prescription. It is a salicylate. It effectively diminishes the pain of problems such as headaches, toothaches and joint pains. It works by reducing substances in the body that cause fever, pain and inflammation. salicylic acid (C7H6O3) + acetic …show more content…

Some product will be dissolved while washing. Cold water is used instead of warm water to reduce the amount of dissolving the product. • The synthesis uses different temperatures because when using warm water, which is at a higher temperature, molecules move more quickly and collide which each other more as they have more kinetic energy which increases the solubility of the aspirin. Using an ice bath slows down the molecules, enabling them crystallize. The aspirin is characterized by melting point at the end. To check whether the product is pure, the melting point range should be minimal. Procedure Synthesis of the aspirin: 1. 2g of salicylic acid is weighed in a dry 100ml conical flask using a top-pan balance. The actual weight is recorded. 2. In the fumehood,5mL of acetic anhydride is added to salicylic acid in the flask. An ester and water will be formed. 3. To this mixture,3-4drops of concentrated sulfuric acid is added and the mixture is swirled. This will speed up the reaction. salicylic acid + acetic anhydride (ethanoic anhydride) [H2SO4] → aspirin (acetylsalicylic acid) + acetic acid (ethanoic …show more content…

The crude product is dissolved completely in 5mL of ethanol to form a hot saturated solution. If necessary, the solution is warmed. Do not let it boil. Recrystallization is performed to purify the aspirin which is usually done by dissolving the substance in a suitable solvent, which is hot. 8. Approximately 30mL of hot distilled water is added into the solution on a hotplate one the solid dissolves. 1mL of ethanol is added and warmed gently if the solid reappears, until the solid dissolves completely. (the solution should be completely clear) 9. The solution is cooled to room temperature and then it is placed in an ice-bath in the fumehood for approximately 10-15mins. The solution is not to be agitated while cooling. Using an ice bath slows down the molecules in the solution, enabling them crystallize. 10. A clean, dry watch glass with two pieces of filter papers are weighed and recorded. 11. The recrystallized products are obtained by suction filtration using our weighed filter paper. 12. The crystals and filter paper are transferred onto the watch glass. At 100degrees Celsius, the crystals are dried for 15-20mins. 13. For 5-10 minutes, the crystals, filter paper and watch glass are placed in a

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