Import Question JSON

$\text{Hint: In a disproportionation reaction, a single element is oxidized and reduced.}$ $(\text{a}) \text{ and } (\text{b}) \text{ are the disproportionation reactions.}$ $\text{In disproportionation reactions, one substance is oxidized and that same substance gets reduced as well.}$ $\text{Analysis of each reaction:}$ $\text{Reaction (a): } 2\text{Cu}^+ \rightarrow \text{Cu}^{2+} + \text{Cu}^0$ $\text{Cu gets oxidized (Cu}^+ \rightarrow \text{Cu}^{2+}\text{) and Cu gets reduced (Cu}^+ \rightarrow \text{Cu}^0\text{). This is disproportionation.}$ $\text{Reaction (b): } 3\text{MnO}_4^{2-} + 4\text{H}^+ \rightarrow 2\text{MnO}_4^- + \text{MnO}_2 + 2\text{H}_2\text{O}$ $\text{MnO}_4^{2-} \text{ gets oxidized into MnO}_4^- \text{ and MnO}_4^{2-} \text{ gets reduced into MnO}_2\text{. This is disproportionation.}$ $\text{Reaction (c): } 2\text{KMnO}_4 \rightarrow \text{K}_2\text{MnO}_4 + \text{MnO}_2 + \text{O}_2$ $\text{Mn gets reduced from +7 to +6 and +7 to +4, and O gets oxidized from -2 to 0.}$ $\text{Since two different elements (Mn and O) undergo redox changes, this is NOT a disproportionation reaction.}$ $\text{Reaction (d): } 2\text{MnO}_4^- + 3\text{Mn}^{2+} + 2\text{H}_2\text{O} \rightarrow 5\text{MnO}_2 + 4\text{H}^{\oplus}$ $\text{Mn oxidation state changes from +7 to +4 and Mn}^{2+} \text{ undergoes from +2 to +4.}$ $\text{This involves different Mn species, so it's NOT disproportionation.}$