Standardization of Na2S2O3
Added 0.12 g KIO3 and dissolved in 75 mL of distilled water. Added .20 g of KI to solution, then added 10 mL of 1M HCl and immediately titrated with thiosulfate solution (made by weighed 25 g of Na2S2O3-5H20 and .1 g of Na2C3 in 1 L of H20 that has been boiling for at least 5 minutes, then cooled solution)added 5 mlo of starch when became yellow, became blue, titrated until blue disappears.
Took 20.52 mL of thiosulfate solution for solution to become clear - what is the molarity of the Na2S2O3?