Question

The equivalent mass of $MnS{O}_4$ becomes half of its molecular mass when it is converted into:

• A. ${Mn{O}_4}^{-}$
• B. $Mn{O}_2$
• C. ${Mn{O}_4}^{2-}$
• D. ${M{n}_2{O}_4}^{2-}$

Answer 1

The correct option is B $Mn{O}_2$

When $\stackrel{(+2)}{MnS{O}_4}$ is converted to $\stackrel{(+4)}{Mn{O}_2}$, the oxidation number changes by $2$, thus
Equivalent mass of $MnS{O}_4=\frac{\text{Molecular mass}}{2}$.