Question

Total number of electrons involved per molecule in the oxidation of $Fe{C}_2{O}_4$ to $F{e}^{3+}$ and $C{O}_2$ is :

• A. $3$
• B. $2$
• C. $4$
• D. none of these

Answer 1

The correct option is A $3$

Total number of electrons involved per mole oxidation of $Fe{C}_2{O}_4$ to $F{e}^{3+}$ and $C{O}_2$ is $3$ moles.
The oxidation of ferrous ions to ferric ions involves $1$ mole of electrons.
$F{e}^{2+}\to F{e}^{3+}+e^{-}$
The oxidation of oxalate ions to carbon dioxide involves $2$ moles of electrons.
$C_2{O}_4^{2-}\to 2C{O}_2+2e^{-}$
Thus, the overall reaction involves $3$ moles of electrons.
$F{e}^{2+}+C_2{O}_4^{2-}\to F{e}^{3+}+2C{O}_2+3e^{-}$