Question

Complete and balance the following chemical equation.
$F{e}^{2+}+Mn{O}_4^{-}+H^{+}\to$

Answer 1

The incomplete, unbalanced chemical equation is.
$F{e}^{2+}+Mn{O}_4^{-}+H^{+}\to$
The complete, unbalanced chemical equation is.
$F{e}^{2+}+Mn{O}_4^{-}+H^{+}\to F{e}^{3+}+M{n}^{2+}+H_{2}O$
Fe atoms and Mn atoms are balanced.
The oxidation number of iron increases from $+2$ (in $F{e}^{2+}$) to $+3$ (in $F{e}^{3+}$). Total increase in oxidation number for iron is $3-2=1$.
The oxidation number of Mn decreases from $+7$ (in $Mn{O}_4^{-}$) to $+2$ (in $M{n}^{2+}$). Total decrease in oxidation number for Mn is $7-2=5$.
To balance total increase in oxidation number with total decrease in oxidation number, add coefficent 5 to iron species.
$5F{e}^{2+}+Mn{O}_4^{-}+H^{+}\to 5F{e}^{3+}+M{n}^{2+}+H_{2}O$
Balance O atoms by adding 3 water molecules to products side.
$5F{e}^{2+}+Mn{O}_4^{-}+H^{+}\to 5F{e}^{3+}+M{n}^{2+}+4H_{2}O$
Balance H atoms by adding 7 protons to reactants side.
$5F{e}^{2+}+Mn{O}_4^{-}+8H^{+}\to 5F{e}^{3+}+M{n}^{2+}+4H_{2}O$
This is the complete, balanced chemical equation.