Aspirin is a painkilling drug and is produced worldwide to reduce and stop pain. Aspirin is made up of ehtanoylation of 2-hydroxbenzenecarboxylic acid in a presence of phosphoric acid. AIM: The aim of the experiment is to prepare and produce aspirin as pure as possible. I will do this threw preparing the aspirin and purifying the product threw recrystallization. I will then obtain a melting point of my product to get an estimate of its purity. By the end of the experiment the target is to produce aspirin as pure as possible. Apparatus for synthesis of aspirin Materials for synthesis of aspirin * Pear shaped flask * 2.0 g of hydrobenzenecarboxylic acid * Fume cupboard * 4 cm3 of ethanoic anhydride * Flask with reflux condenser * 5 drops of phosphoric acid * Water bath * ice * 100 cm3 beaker * distilled water* Pipette * boiling water* Funnel * Filter paper* Spachelor * Kettle*Weighing boat*Boiling tube|
Apparatus for melting point Materials for melting point*Capillary tube *Tesco aspirin*Melting apparatus * synthesised aspirin| Apparatus for chromatography Materials for chromatography *Chromatography tank *Ethanol dichloromethane *Capillary tubes * Tesco pure aspirin *Weighing boat * Recrystallized aspirin *TLC paper * DCM
Production of Aspirin
1) Weigh out around 2.0g of hydrobenzenecarboxylic acid
2) Put 4cm3 of ethanoic anhydride into a pear shaped flask
3) Add the 2 –hydroxbenzenecarboxylic acid to the pear shaped flask a well and mix. 5) In a fume cupboard, add 5 drops of phosphoric acid to the reaction mixture in the pear shaped flask and swirl to mix 6) Set up a flask with a reflux condenser
7) Without cooling, add 2cm3 of water down the condenser. This will react with any excess ethanoic anhydride in a vigorous reaction. This will allow the product to become more pure. 8) When the reaction of the excess ethanoic anhydride with water has finished, pour the mixture into 40 cm3 of cold water in a 100 cm3 beaker and allow cooling to room temperature. 9) Complete crystallization by placing the beaker and its contents in an ice bath. If necessary scratch the sides of the beaker with a glass rode to induce crystallization. 10) Collect the product by suction filtration and wash with a little water. Suction and filtration involves filter paper and a funnel for the excess impurity’s to drain out. Evaluation of production of aspirin
The experiment went overall well, and the production of aspirin went to plan. We were able to use all the apparatus and measure out materials independently and accurately. The crystals where perfectly formed and we gained a large amount. The only problem was when filtering out the product we forgot to add filter paper .This may have reduced purity and left unwanted products , so next time we carry out the experiment we shall insure we use filter paper. Also we will cool the aspirin more slowly to increase the crystals size. I would estimate that my product is 95 % pure because we measured and carried the...