Question

SYNT 439: Synthesizing Aspirin Post - Laboratory Questions (Use the spaces provided for the answers) 1. (1) A student who was in a hurry to complete this experiment did not completely dry the crystalline product before doing the final weighting. How would this error affect the calculated percent yield of the experiment? The results Hughes weight because the crystal has some moisture. It can be added in to own original product weight. So it results high molecular weight. So we got high yield. (2) What is the purpose of adding 10 mL of ice water to the Erlenmeyer flask? (3) The student in (1) mixed the crystalline product with ethanolic 1% FeCl: solution and obtained a colored solution. Briefly explain what might have caused this result. FeCl3 indicates the presence of phenol group. It creates or produces purple color. It results improper heating and the sample is impure. (4) What is the reason for stirring the sample with a glass rod after you remo bath? Paused To I deuce crystallization

number 2

Answer 1

2) Ice water is added to remove the excess of acetic anhydride or acetic acid which is added as catalyst in the reaction and to crystallize the aspirin (Aspirin is not very soluble in water that to in ice cold water is very less).