[CHEM 1120]LAB#6: Synthesis of Acetylsalicylic Acid

LAB #6 : SYNTHESIS OF ACETYLSALICYLIC ACID
DATA
MASS OF SALICYLIC ACID ___2.182 g____
MASS OF 50 mL FLASK ___41.039 g___


MASS OF ASPIRIN (determination of yield) ___1.725 g____
MASS OF EMPTY 100 mL BEAKER ___47.755 g___
MASS OF 100 mL BEAKER + ASPIRIN ___49.480 g___


COLOUR OF TESTED ASPIRIN WITH FERRIC CHLORIDE __clear____
COLOUR OF TESTED SALICYLIC ACID WITH FERRIC CHLORIDE ___purple___



CALCULATIONS
1. Theoretical Yield:
Salicylic Acid + Acetic anhydride → Aspirin + Acetic Acid
C7H6O3 C4H6O3 C9H804 C2H4O2



1 mol C7H6O3 1 mol C9H8O4 181.1 g C9H8O4
2.182 g C7H6O3 × × × = 2.861 g C9H804
138.1 𝑔 1 mol C7H603 1 mol




actual yield 1.725 g
2. Percent Yield: %= × 100% = × 100% = 60.29%
theoretical yield 2.861 g

3. Ferric chloride test on salicylic acid : PURPLE Ferric chloride test on aspirin: CLEAR

4. Ferric chloride reacts with phenol functional groups. Since phenol is part of the salicylic acid
molecule, the test with ferric chloride produces a deep purple colour. When the phenol group is
substituted with an ester group, the ferric chloride produces a clear colour.