# Chem.

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An aspirin tablet weighing 0.400 g has been analyzed and contains 68.2 % ASA (180.16 g/mol) by mass. A student dissolved
the tablet in hot NaOH and the cooled solution was diluted with DI water to the mark in a 250 mL volumetric flask. Exactly 3.00 mL
of the solution was pipetted into a 100 mL volumetric flask and diluted to the mark with FeCl3 solution.
The concentration of the diluted solution is

• Chem. -

The concn of what in the diluted solution? the original sample or the ASA in the original sample? And what kind of units for the concn?
The original sample is
(0.400 g/250 mL) x (3 mL/100 mL) = ?? g/mL

If you want the concn ASA, you start with 0.4 x 0.682 = ?? and use that number in place of the 0.400 g.

If you want molarity, change the first solution to molarity.
0.400 x 0.682 x (1 mol/180.16 g) x 1000 mL/250 mL then the dilution is x (3 mL/100 mL) = ?? M.
Check my work.

• Chem. -

Your work is correct, DrBob222. Thanks for the help

• Chem. -

so whats the actual answer for the concentration? i keep trying and im getting the wrong answer.