When 25 mL of a solution which is having both Fe3+ and Fe2+ ions is titrated with the 23 mL of 0.02 M KMnO4 all of the Fe2 ions are oxidized to the Fe3+ ions.
Next, the solution is treated with Zn metal to convert all of the Fe3+ ions to Fe2+ ions.
Finally, 40 mL of the same KMnO4solution are added to the solution in order to oxidize the Fe2+ions to Fe3+.
Determine the molar concentrations of Fe3+ and Fe2+ in the original solution.