Question

Which of the following stlatement(s) is/are correct.

• A. $0.2moles$ of $KMn{O}_4$ will oxidise one mole of ferrous ions to ferric ions in acidic medium.
• B. $1.5$ moles of $KMn{O}_4$ will oxidise $1$ mole of ferrous oxalate to one mole of ferric ion and carbon dioxide in acidic medium in acidic medium
• C. $0.6$ moles of $KMn{O}_4$ willoxidise $1$ mole of ferrous oxalate to one mole of ferric ion and carbon dioxide in acidic medium
• D. $1$ mole of $K_{2}C{r}_2{O}_7$ will oxidise $2$ moles of ferrous oxalate to ferric ions and carbon dioxide in acidic medium

Answer 1

Answer: (A), (C), (D)

$1$ mole of $K_{2}C{r}_2{O}_7$ will oxidise $2$ moles of ferrous oxalate to ferric ions and carbon dioxide in acidic medium

$Mn{O}_4^{-}+5e^{-}+8H^{+}\to M{n}^{2+}+4H_{2}O$
1 mole of $Mn{O}_4^{-}$, accepts 5 mole of $e^{-}$
$\frac{1}{5}$mole of $Mn{O}_4^{-}$, accepts 1 mole of $e^{-}$
$0.2$ mole of $Mn{O}_4^{-}$, accepts 1 mole of $e^{-}$
$0.6$ mole of $Mn{O}_4^{-}$, accepts 3 mole of $e^{-}$
$F{e}^{2+}\to F{e}^{3+}$
1 mole of $F{e}^{2+}$ will liberate 1 mole of $e^{-}$
$C{r}_2{O}_7^{2-}+6e^{-}+14H^{+}\to 2C{r}^{3+}+7H_{2}O$
1 mole of $C{r}_2{O}_7^{2-}$ will accept 1 moles of $e^{-}$
1 mole of $Fe{C}_2{O}_4\to F{e}^{3+}+C{O}_2+3e^{-}$
1 mole of ferrous oxalate gives 3 moles of $e^{-}$
$0.2$ mole of $Mn{O}_4^{-}$=$\frac{1}{5}$mole of $Mn{O}_4^{-}$ oxidises 1 mole of $F{e}^{2+}ions$(Tallies with statement a)
$0.6$ mole of $Mn{O}_4^{-}$ will oxidise $\frac{3}{5}$mole of $Mn{O}_4^{-}$ oxidises 1 mole of ferrous oxalate.(Tallies with statement c)
1 mole of $C{r}_2{O}_7^{2-}$ will oxidise 2 mole of ferrous oxalate.(Tallies with statement d)
Hence, (a), (c), (d) are correct whereas (b) is incorrect