Chemistry - Redox Reactions Question with Solution | TestHub

$\therefore 4{\mathrm{OH}}^{-}\to 2{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2+4{\mathrm{e}}^{-}$ for 2 mole of ${\mathrm{H}}_2\mathrm{O}=4\mathrm{F}$ charge is required for 1 mole of ${\mathrm{H}}_2\mathrm{O}=\frac{4F}{2}=2\mathrm{F}$ required $\stackrel{+7}{{\mathrm{MnO}}_4^{-}}\to \stackrel{+2}{\mathrm{Mn}}{}^{2+}$ for 1 mole ${\mathrm{MnO}}_4^{-}5\mathrm{F}$ charge is required ${\mathrm{Ca}}^{2+}\stackrel{+2{\mathrm{e}}^{-}}{\to }\mathrm{Ca}$ For 1 mole ${\mathrm{Ca}}^{2+}$ ion required $=2\mathrm{F}$ 1.5 mole ${\mathrm{Ca}}^{2+}$ ion required $=\frac{2}{1}\times 1.5=3\mathrm{F}$ $\stackrel{+2}{\mathrm{FeO}}\to \stackrel{+3}{\mathrm{Fe}}{\mathrm{O}}_2{\mathrm{O}}_3$ for 1 mole $\mathrm{FeO},1\mathrm{F}$ charge is required.