A 50-mL solution of 0.5005 N standard NaOH was added to a 0.9250-g sample of Aspirin and was boiled for 10 minutes. After cooling a full pipet of phenolphthalein was added to the solution before it was titrated with 24.7 mL of 0.5015 N standard HCl solution until the disappearance of the pink color. The same procedure was carried using a blank which consumed 4.6 mL of the same standard acid. Calculate for the %Aspirin in the sample. Atom weights: C =12, H =1, O =16.

A 50-mL solution of 0.5005 N standard NaOH was added to a 0.9250-g sample of Aspirin and was boiled for 10 minutes. After cooling a full pipet of phenolphthalein was added to the solution before it was titrated with 24.7 mL of 0.5015 N standard HCl solution until the disappearance of the pink color. The same procedure was carried using a blank which consumed 4.6 mL of the same standard acid. Calculate for the %Aspirin in the sample. Atom weights: C =12, H =1, O =16.

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter12: Chemical Equilibrium

Section12.3: Determining Equilibrium Constants

Problem 12.3PSP

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