In Iodometry, I already know that I- will be oxidized to I2 if titration of Cu(II) is not done immediately, but what effect does it have to the molarity of S2O3^2-?

Answer 1

Are you standardizing thiosulfate with Cu metal? Then air oxidizes I^- to free I2 and that takes more thiosulfate in the titration; therefore, volume of thiosulfate is too large and molarity is too ???

Answer 2

low.. thanks!