Question

$KMnO_4$ reacts with ferrous ammonium sulphate according to the equation $MnO_4^{-}+ 5Fe^{2+} + 8H^{+} \to Mn^{2+}+5Fe^{3+} + 4H_2O,$ here $10 ml$ of $0.1 M KMnO_4$ is equivalent to

• A. $20\, ml\, of\, 0.1\, M\, FeSO_4$
• B. $30\, ml\, of\, 0.1\, M\, FeSO_4$
• C. $40\, ml\, of\, 0.1\, M\, FeSO_4$
• D. $50\, ml\, of\, 0.1\, M \,FeSO_4$

Answer 1

Answer: (D)

$KMnO_4 =$ Mohr salt
$\frac{M_{1}V_{1}}{n_{1}}=\frac{M_{2}V_{2}}{N_{2}};\frac{0.1\times10}{1}=\frac{M_{2}V_{2}}{5};M_{2}V_{2}=5.$