Question

The species given below that does $NOT$ show disproportionation reaction is:

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Answer 1

A reaction in which atom of same element is simultaneously oxidised as well as reduced is called a disproportionation reaction. In $Br{O}_4^{-},$ Br is in the highest oxidation state of $+7$, so it cannot be oxidised further. Hence, it cannot show disproportionation reaction.