Which of the following is`//`are disproportionation redox changes?

Options

A. `(NH_(4))_(2) Cr_(2)O_(7) rarr N_(2)+Cr_(2)O_(3)+4 H_(2)O`
B. `5H_(2)O_(2)+2 ClO_(2)+2 overset(ɵ)(OH) rarr 2 Cl +overset(ɵ)(%)O_(2)+6H_(2)O`
C. `3 ClO^(ɵ) rarr ClO_(3)^(ɵ)+Cl^(ɵ)`
D. `2HCuCl_(2) overset("Dilution")underset("with water")(rarr) Cu+Cu^(2+)+4Cl+.^(ɵ)2H^(o+)`

Answer

C, D

Explanation

(c) `2e^(-) + ClO^(Θ) rarr Cl^(Θ)` (Reduction)
`x -2 = -1 " " x = -1`
`x = +1`
`ClO^(Θ) rarr ClO_(3)^(Θ) + 4e^(-)` (Oxidation)
`x = 1 " " x = 5`
(d) In `HCuCl_(2), Cu` is in +1 oxidation state which disproportionates to `Cu^(2+) and Cu^(0)`