# When using the esterification process to synthesize aspirin, how do you calculate the theoretical yield of aspirin using 4.00 grams of salicylic acid. Assume acetic anhydride is in excess. The...

When using the esterification process to synthesize aspirin, how do you calculate the theoretical yield of aspirin using 4.00 grams of salicylic acid. Assume acetic anhydride is in excess. The molecular weight of salicylic acid is 138 grams per mole and aspirin is 180 grams per mole. The limiting reagent for this reaction will be salicylic acid. Since the salicylic acid : molar ratio is 1:1, then 1 mole of salicylic acid will produce one mole of aspirin.

Reaction molecular formula: C7H603 + C4H6O3 --> C9H8O4 + C2H4O2

gsenviro | Certified Educator

Using the given synthesis reaction of aspirin (C9H8O4) from salicylic acid (C7H6O3),

C7H6O3 + C4H6O3   ---> C9H8O4   + C2H4O2

Using the given information that acetic anhydride (C4H6O3) is in excess and that salicylic acid will be the limiting agent:

Using stoichiometry: 1 mole of salicylic acid produces 1 mole aspirin

or using the molecular weights

138 gm salicylic acid -----> 180 gm aspirin

Using unitary method,

1 gm salicylic acid ------> 180/138 gm aspirin

and 4 gm salicylic acid  ---------> 4 x 180/138 gm aspirin  = 5.22 gm aspirin