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A 4.0 g sample contained Fe2O3,Fe3O4, an...

A 4.0 g sample contained `Fe_2O_3,Fe_3O_4`, and inert material. It was treated with an excess of aq KI solution in acidic medium, which reduced all iron to `Fe^(2+)` ions along with the liberation of iodine . The resulting solution was diluted to 50 mL and a 10 mL sample of it was taken the iodine liberated in the small sample was titrated with 12.0 " mL of " 0.5 M `Na_2S_2O_3` solution. The iodine from another 25 mL was extracted, after which the `Fe^(2+)` ions were titrated with 16 " mL of " 0.25 M `MnO_4^(ɵ)` ions in `H_2SO_4` solution. Calculate the mass of two oxides in the original mixture.

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The correct Answer is:
`24.67%`
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