Choose the group of ions / molecules in which none of the species undergo Disproportionation reaction.

Step-by-step solution

A disproportionation reaction occurs when an element in a specific oxidation state is simultaneously oxidized and reduced. This requires the element to be in an intermediate oxidation state, meaning it must be capable of both increasing and decreasing its oxidation state. Analyzing the species in option (r4BrP): 1. Cr ₂ O ₇²⁻ : The oxidation state of Cr is +6 , which is the maximum possible oxidation state for Chromium. It cannot be further oxidized, so it cannot undergo disproportionation. 2. F ₂ : Fluorine is the