JEE Main 2025 · Chemistry · d- and f-Block Elements and Metallurgy · medium

In acidic medium, the number of moles of KMnO4 required to oxidise completely 1 mole of ferrous oxalate, FeC2O4, is

Single correct option

In acidic medium, the number of moles of

\mathrm{KMnO_4}

required to oxidise completely

1

mole of ferrous oxalate,

\mathrm{FeC_2O_4}

, is

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Answer: (C) $0.6$

Both ions are oxidised:

\mathrm{Fe^{2+}\to Fe^{3+}}

loses

1\ e^-

and

\mathrm{C_2O_4^{2-}\to 2CO_2}

loses

2\ e^-

, so

3

equivalents per mole of

\mathrm{FeC_2O_4}

\mathrm{MnO_4^-}

gains

5\ e^-

in acid (

\mathrm{Mn^{7+}\to Mn^{2+}}

). Moles of permanganate

=3/5=0.6

. Counting only oxalate gives

0.4

, only iron

0.2

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