Which of the following reactions are disproportionation reactions?
`(A)" " Cu^(+)rarrCu^(2+)+Cu`
`(B)" "3 MnO_(4)^(2-)+4H^(+)rarr2MnO_(4)^(-)+MnO_(2)+2H_(2)O`
`(C )" "2KMnO_(4)rarrK_(2)MnO_(4)+MnO_(2)+O_(2)`
`(D)" "2MnO_(4)^(-)+3Mn^(2+)+2H_(2)O rarr5MnO_(2)+4H^(+)`

Options

A. I,II
B. I,II,III
C. II,III,IV
D. I,IV

Answer

A

Explanation

In (I), `Cu^(+)` is oxidised as well as reduced. In (II), `MnO_4^(-)` ions are oxidised as well as reduced.