The amount of I3−(aq) in a solution can be determined by titration with a solution containing a known concentration of S2O32−( aq ) (thiosulfate ion). The determination is based on the net ionic equation 2 S2O32−(aq)+I3−(aq)⟶S4O62−(aq)+3I−(aq) Given that it requires 35.5 mL of 0.360MNa2 S2O3 (aq) to titrate a 20.0 mL sample of I3−(aq), calculate the molarity of I3−(aq) in the solution. [I3−]= M