Question

In the synthesis of aspirin from salicylic acid and excess acetic anhydride, you start with 3.56 g of sailicylic acid and recover 3.21 g of aspirin. What is (a) your theoretical yield (b) your actual yield and (C) your percent yield?

Answer 1

To calculate the theoretical yield, determine the limiting reagent and use stoichiometry. The actual yield is what was obtained in the experiment, and the percent yield is calculated by dividing the actual yield by the theoretical yield and multiplying by 100. The percent yield is (3.21 g / 5.71 g) x 100 = 56.27%.

Step-by-step explanation:

To calculate the theoretical yield, you need to determine the limiting reagent in the reaction. In this case, the limiting reagent is salicylic acid because it is provided in a limited amount. The molar ratio between salicylic acid and aspirin is 1:1, so the theoretical yield can be calculated by converting the mass of salicylic acid to moles and then to grams of aspirin. The molar mass of salicylic acid is 138.12 g/mol, so 3.56 g of salicylic acid is equal to 0.0258 moles. Therefore, the theoretical yield of aspirin is 0.0258 moles or 5.71 g.

The actual yield is the amount of the desired product obtained in the experiment, which in this case is 3.21 g of aspirin.

The percent yield is calculated by dividing actual yield by theoretical yield and multiplying by 100. In this case, the percent yield is (3.21 g / 5.71 g) x 100 = 56.27%.