Question

1.) To standardize a thiosulfate (S₂O₃^2-) solution, 10.00 mL of a  1.25×10⁻² M   IO₃^- solutionare treated with excess I^- to generate I₃^- according to the following equation:
IO₃^-(aq) + 8I^-(aq) + 6H⁺ --> 3I₃^- + 3H₂O(l)
If  5.83 mL of the thiosulfate solution are required to reach the endpoint of the titration, what is the molarity of thiosulfate in the solution? Report your answer to 3 significant figures. The following equation might be helpful:
I₃^-(aq) + 2S₂O₃^2-(aq) --> 3I^-(aq) + S₄O₆²(aq)

2.)   2.15 g of bleach solution are treated with excess I^- to generate I₃^- according to the following equation:
ClO^-(aq) + 3I^-(aq) + H₂O(l) --> I₃^-(aq) + Cl(aq) + 2OH-(aq)
27.02 mL of the standardized thiosulfate solution in Part 1 are required to reach the endpoint of the titration. What is the mass percent of NaClO in the bleach solution? (Report your answer to 3 significant figures. The following equation might be helpful:
I₃^-(aq) + 2S₂O₃^2-(aq) --> 3I^-(aq) + S₄O₆²(aq)

Thank you for your help xx

Answer 1