Question

How many moles of $MnO _{4}^{-} \& Ca ( OH )_{2}$ are required to react with 1 mole of $Fe \left( HC _{2} O _{4}\right)_{2}$ respectively?

• A. 2, 1
• B. 3, 1
• C. 1 , 1
• D. 2, 2

Answer 1

Answer: (A)

$30 H ^{+}+5 MnO _{4}^{-}+5 Fe \left( HC _{2} O _{4}\right)_{2} \rightarrow 5 Mn ^{2+}+5 Fe ^{3+}+$

$20 CO _{2}+20 H _{2} O$

From here it is evident that 1 mole of $5 MnO _{4}^{-}$ is required to react with 1 mole of $Fe \left( HC _{2} O _{4}\right)_{2}$

$Ca ( OH )_{2} \rightleftharpoons Ca ^{2+}+2 OH ^{-}$

$Fe \left( HC _{2} O _{4}\right)_{2} \rightleftharpoons Fe ^{2+}+2 HC _{2} O _{4}^{-}$

$2HC_2O_4^- \rightleftharpoons 2H^+ + C_2O_4^{2-}$

One mole of $Fe \left( HC _{2} O _{4}\right)_{2}$ will furnish 2 mole of $H ^{+}$ which require 1 mole of $Ca ( OH )_{2}$

It is not a redox reaction it is rather a neutralisation reaction.