Question

I understand part a, I need help with B and C. Thanks!

6-B. Vitamin C (ascorbic acid) from foods can be measured by titration with 13: CH4O6 + + H2O = C,H,O + 30 + 2H Ascorbic acid Triiodide Dehydroascorbic acid FM 176.126 Starch is used as an indicator in the reaction. The end point is marked by the appearance of a deep blue starch-iodine complex when unreacted 15 is present. (a) If 29.41 mL of Iz solution are required to react with 0.197 0 g of pure ascorbic acid, what is the molarity of the Iz solution? (b) A vitamin C tablet containing ascorbic acid plus inert binder was ground to a powder, and 0.4242 g was titrated by 31.63 mL of 13. How many moles of ascorbic acid are present in the 0.424 2-g sample? (c) Find the weight percent of ascorbic acid in the tablet.

Answer 1

I moles of used & moles of ascorble and mass molar mass (mx) = 0.19409 0.19709 176 129/mol m - x 29-4ml xion = 0.001118 moleJ 2) Molarity of 15 m = 0.03509 m. 2 10-03803 m. acide moles of In moles of ascorbi 20-03803 mx 3163M4 x 16 001203 moles moles d ascorbic and c) mass d as cable and 2 0.001203 moles x 176.12 9 mol 20. 2119 9 f = weight x 100 f. mass mass d of ascorble act sample o 21199 O-42429 X1007 - 149-957