To obtain the maximum yield of acetylsalicylic acid ASA during the preparation process using acetic anhydride and salicylic acid, you should follow these steps:1. Stoichiometry: Ensure that the stoichiometry of the reaction is correct. The balanced chemical equation for the synthesis of ASA is: C7H6O3 salicylic acid + C4H6O3 acetic anhydride C9H8O4 acetylsalicylic acid + C2H4O2 acetic acid This means that one mole of salicylic acid reacts with one mole of acetic anhydride to produce one mole of ASA. Calculate the required amounts of each reactant based on their molar masses and the desired yield of ASA.2. Purity of reactants: Ensure that the reactants, salicylic acid and acetic anhydride, are of high purity. Impurities can decrease the yield of ASA and may cause side reactions.3. Temperature: The reaction should be carried out at an optimal temperature, typically around 85-90C. This temperature is high enough to facilitate the reaction but not too high to cause decomposition of the reactants or products.4. Catalyst: Use a catalyst, such as concentrated sulfuric acid or phosphoric acid, to increase the reaction rate and improve the yield of ASA. The catalyst should be added in a small amount a few drops to avoid side reactions.5. Reaction time: Allow the reaction to proceed for an appropriate amount of time, typically around 15-20 minutes, to ensure the completion of the reaction.6. Quenching the reaction: After the reaction is complete, quench it by adding cold water or an ice bath. This will help to precipitate the ASA and stop any further reactions.7. Filtration: Filter the reaction mixture to separate the solid ASA from the liquid acetic acid and any unreacted reactants. Use a vacuum filtration setup for faster and more efficient filtration.8. Washing and drying: Wash the collected ASA with cold water to remove any remaining impurities, and then dry it using a vacuum desiccator or by air-drying in a well-ventilated area.9. Recrystallization: To further purify the ASA and obtain a higher yield, perform a recrystallization using a suitable solvent, such as ethanol or a mixture of ethanol and water. This will help to remove any remaining impurities and improve the overall yield of ASA.By following these steps and optimizing the reaction conditions, you can maximize the yield of acetylsalicylic acid during the preparation process using acetic anhydride and salicylic acid.