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A 1.5380g sample of iron ore is dissolved in acid，the iron is reduced to the +2 oxidation state quantitatively and titrated with 43.50mL of KMnO4solution(Fe2+→Fe3+),1.000 mL of which is equivalent to 11.17 mg of iron． Express the results of the analysis as (1)w(Fe)；(2)w(Fe2O3)；(3)w(Fe3O4)．
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