Question

Aspirin tablet, mass of tablet= 0.4149 g concentration of iron III salicylate complex = 3.997E-4, What is the concentration of ASA in the original solution? What is the mass of ASA in the original solution?

The procedure was as follows: accurately weigh by difference a tablet and transfer it into a 125ml erlnemyer flask, add 20 ml of 0.5 M NaOH and gently heat the mixture to boiling, Transfer the solution to a 100 ml volumetric flask and dilute the solution with water to the 100ml mark, pipet 2ml of the solution into a 100 ml volumetric flask and dilute to 100ml mark with 0.02 M iron III chloride Solution.