Question

Which of the following reactions are disproportionation reactions?
(I) $C{u}^{+}\to C{u}^{2+}+Cu$
(II) $3Mn{O}_4^{-}+4H^{+}\to 2Mn{O}_4^{-}+Mn{O}_2+2H_{2}O$
(III) $2KMn{O}_4\to K_{2}Mn{O}_4+Mn{O}_2+O_2$
(IV) $2Mn{O}_4^{-}+3M{n}^{2+}+2H_{2}O\to 5Mn{O}_2+4H^{+}$

• A. (I), (II)
• B. (I), (II), (III)
• C. (II), (III), (IV)
• D. (I), (IV)

Answer 1

Answer: (A)

In $(I)$, $C{u}^{+}$ is oxidised as well as reduced. In $(II)$, $Mn{O}_4^{-}$ ions are oxidised as well as reduced.