C7H6O3 + CH3COOH —> C9H8O4 + H2O

Question

C7H6O3 + CH3COOH —> C9H8O4 + H2O
The above reaction between salicylic acid (C7H6O3) and acetic acid shows the synthesis of aspirin (C9H8O4). If the percent yield of the reaction is 33.3% then what mass of aspirin could be recovered from the reaction of 18.8 g of salicylic acid?
Thanks for your help!

Answer 1

Hello Divine

 

The mass of aspirin recovered from this reaction is referring to the "actual yield."

 

Let's first calculate the Theoretical Yield (TY) of aspirin starting with 18.8 g of Salicylic acid.  Molar mass of salicylic acid is 138 g/mol, molar mass of aspirin is 180 g/mol, and the mole ratio of salicylic acid to aspirin is 1:1.  I am going to abbreviate SA for salicylic acid, and Asp for aspirin in the TY calculation.

 

18.8 g SA x (1 mol SA / 138 g SA) x (1 mol Asp / 1 mol SA) x (180 g Asp / 1 mol Asp) = 24.5 g Asp

 

TY of Asp = 24.5 g

 

%-Yield = (Actual yield / Theoretical yield) x 100%

 

Actual yield = %-Yield x Theoretical yield

 

                     = 33.3% x 24.5 g

 

                     = 0.333 x 24.5 g

 

                    = 8.16 g Aspirin recovered