Synthesis of aspirin mechanism with sulfuric acid
The percent yield of the crude product will be determined for this reaction. Calculating the Percent Yield of Aspirin A. Dissolve the final product in a minimum amount no more than mL of hot ethyl acetate in a 25 mL Erlenmeyer flask. Remove all the liquid from the crystals by pressing with a clean stopper or cork. Place the filter paper with the product in a watch glass and put it in the oven at oC for about 30 min. A large melting point range would suggest an impure sample and ineffective recrystallization process. Do this test with 1. In this lab, for recrystallization, the solution was allowed to cool to room temperature very slowly, but was then plunged rapidly into ice water. Right click a data point and select add trend line. If acetylsalicylic acid does not begin to crystallize out, scratch the walls of the flask with a glass rod. Notify the teacher immediately in the event of a spill. When the crystals are all dissolved, add 10 mL of deionized water, cover the beaker with a watch glass, and allow the solution to cool slowly on the lab bench undisturbed for about 10 minutes. Student Worksheet PDF. Clearly state if the samples are below the maximum allowable limit for percent salicylic acid 0.
Wear gloves when using these chemicals. Do not inhale the vapors. Allow the Erlenmeyer flask to cool, then add 3 mL of ice-cold water from step 8 dropwise to the reaction mixture.
Put the dry aspirin and the filter paper into a pre-weighed plastic bag and weigh again. Lower absorbance values would indicate that a greater concentration of phenol was present and the absorbance value could be used to directly determine the concentration 1 Cappelli, G.
Acetic anhydride is a lachrymator.
Aspirin synthesis equation
Procedure: 1. In this experiment, the crude product will be the desired product. Air dry the crystals and transfer them to a watch glass to dry. When there is no more liquid in the funnel, carefully remove the filter paper and scrape the crystals onto the preweighed watch glass. Hoffman's father had severe arthritis but could not tolerate salicylic acid he was taking for pain relief. General Mechanism for an acidic catalyst The personal times measured for the rise in temperature are relatively accurate in relation to the class average results, as the recorded times fall within one standard deviation of the mean. Using a clean circle of filter paper, collect the purified aspirin by suction filtration as before. When most of the liquid has passed through the funnel, rinse any remaining crystals from the flask into the funnel with a small amount no more than 4 mL of ice-cold water. Report Report the theoretical yield and the percent yield of the aspirin product. At your lab bench, assemble a hot water bath using a or mL beaker and place the flask in the water bath as shown in Figure 1. Place a clean beaker or flask under the funnel to collect the filtrate. A vinegar smell may be noticed.
H2SO4 use a dropper, H2SO4 is highly corrosive and swirl the flask gently until the salicylic acid dissolves. The aspirin is then collected, purified by recrystallization, and its melting temperature measured.
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