Question

2. A 0.1000 g sample of KBrO3 was dissolved in dilute acid and treated with an excess of KI. BrO3 +91 +6H+ → Brº+ 313 + 3H20 The generated 13. required 11.92 mL of a Na2S2O3 solution to reduce it to 1. Use the above balanced equation and those found in the introduction to determine the molarity of the Na2S2O3 solution. 3. The following data was obtained for an iodometric titration of an ascorbic acid tablet. Mass of tablet: 1.2191 g Mass of sample analyzed: 0.3009 g Vol. of 0.0200 mol L 1 KIO3: 25.00 mL Vol. of 0.0200 mol.L- Na2S2O3 to reach endpoint: 9.90 ml Using the equations found in the introduction, determine: the mass of ascorbic acid in the sample analyzed and the mass of ascorbic acid contained within the tablet.

Answer 1

Boz &gi + 6H I mole mole af kpr 03 = Br +31 - + 3H₂O - 3 mole gram molarmoSS . 1678/mol = .005 989 =1006 mole KB.Oz = .006 mol 603 il mole Booň = a. 006 1 - 3 mole Iz 34.006 = ola mol Iz 6 Nal & 6503 2 Iz + 3 Na, S₂O3 - 2 mole - 3 mole v 018 - 027 male 11 molarity = wmobiles 1027 mole Na2503 - tit. Volumulit - 2.265 Molellit = 2. 3M Nassou are