Answer to Question #36525 in Chemistry for Sytwu

Question

The determination in problem 15-9 was modified to use the standard addition method. In this case, a 4.236 g tablet was dissolved in sufficient 0.10M HCl to give 1.00 L. Dilution of 20.00 mL aliquot to 100 mL yielded a solution that gave reading of 448 at 347.5 nm. A second 20.00 mL aliquot was mixed with 10 mL of 50 ppm quinine solution before dilution to 100 mL. The fluorescence intensity of this solution was 525. Calculate the percentage of quinine in the tablet.