Question

A 0.300 g sample of an aspirin tablet is used to prepare 100.0 mL of a stock solution by dissolving the tablet in 1 M NaOH then diluting with distilled water to the 100 mL mark of a volumetric flask. A 0.30 mL sample of the stock solution is then transferred to a volumetric flask and diluted with 0.02 M iron(III) chloride to the 10.00 mL mark. The tetraaquasalicylatoiron(III) complex concentration in this 10.00 mL sample is determined to be 4.3x10-4M. What is the percentage of acetylsalicylic acid in the original aspirin tablet? Do not include the % sign in your answer. For example, for a value of 100% enter 100.