Question

Experiment 11: Synthesis of Aspirin pre-lab (4 pts) 1) (2 pts) Refer to the introduction on interpreting the ferric chloride test for phenols. Two students performed the aspirin synthesis experiment. Their melting point and ferric chloride test data are shown below. Based on the results, which student's aspirin has the higher purity? Justify your choice using the melting point data and ferric chloride test results. Melting point range for pure aspirin = 136-140 °C. Melting point range (°C) Ferric chloride test Student A 132 - 142 purple Student B 135 - 139 clear / faint yellow 2) (2 pts) The reaction for the synthesis of aspirin is shown below: OH 0 0 НАРО, HC och HC OH он Acetic anhydride Salicylic acid d = 1.082 g/mL 0CH, MM = 138.12 g/mol MM = 102.09 g/mol Aspirin (acetyl salicylic acid) MM = 180.16 g/mol A student starts with 1.5 g of salicylic acid and 5.0 mL of acetic anhydride. She recovers 0.79 g! of aspirin (product). Determine the following... - theoretical yield -% yield [% yield = (actual yield /theoretical yield) x 100%] *Show your calculations!*

Answer 1

Reagent Identification of Liniting - K Holes of saycitic acid we Molar 1988 (9/ Pole = 1:59 139.62 glmaie = 0.01086 Holes ( Mole = loco Metroles con - 10.86 Motoles acetic anhydride = density X volume .082x5 weight of = 5.41 ghs. hores of Acericanhydride = weight (9) Holar mu88 (glhole) . : Ne 5.41 102.09 = 0.0529 Holes oy 52. a Minoles

.. Among the two Reactant & lead Nutiber of Moles. This the ciniting Reagent. salyclic acid has salycilic acid is calculation of theoretical yield (loot yield): Aspirin 138.12 1. 5 978 of sulycilic and produces 180.169 is of 9 no of salycilic acid produces a onea grs of Aspirin - 1.5x 180.16 138.12 = 1,956 9h8 of aspirin ã 1.96 Theoretical yield = 1.96 g

calculation of to of yield: snental weight 1. of Yield Experinental weight theoretical weight x 100 = 0.799 x 100 1.969 z 40.3 % of yields_40034