Q.

The species which does not undergo disproportionation reaction is :                    [2025]
 

1 ClO2-  
2 ClO3-  
3 ClO-  
4 ClO4-  

Ans.

(4)

Cl+1O-, Cl+3O2-, Cl+5O3-, Cl+7O4-

Cl cannot be oxidized beyond +7 oxidation state, so Cl+7O4- cannot undergo disproportionation.