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Excess of acetic anhydride

What do they mean by using 55.0% excess of acetic anhydride?


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Stoichiometry Problem with Aspirin: Mole/Mole and Percent Yield


Aspirin, C9H8O4, is prepared by reacting salicylic acid, C7H6O3, with acetic anhydride C4H6O3.

C7H6O3 + C4H6O3 -----> C9H8O4 + C2H4O2

Prepare 45.0g of aspirin. Use 55.0% excess of acetic anhydride and expect 85% yield in the reaction. How many grams of each reactant should we use?

Solution: We need to work backwards from 45.0 grams of aspirin. ...

Solution Summary

55.0% excess of acetic anhydride is explained using various equation examples.