Ammonium iron(II) sulfate crystals have the formula

CHEMISTRY · Subjective · CBSE · Chemistry · Redox Reactions · Redox Reactions

Problem

(\mathrm{NH_4})_2\mathrm{SO_4}\cdot\mathrm{FeSO_4}\cdot n\mathrm{H_2O}

. In an experiment to find

n

8.492\,\mathrm{g}

of the salt were dissolved and made up to

250\,\mathrm{cm^3}

with distilled water and dilute sulfuric acid in a volumetric flask. A

25.0\,\mathrm{cm^3}

portion of the solution was titrated against

0.0150\,\mathrm{mol\,dm^{-3}}

\mathrm{KMnO_4}

, requiring

22.65\,\mathrm{cm^3}

. Calculate

n