Consider the following perhalate ion in acidic medium Cl O 4 - I , Br O 4 - II , I O 4 - III Arrange these in the decreasing order of oxidizing power.

Step-by-step solution

Standard reduction potential (in volts) of the perhalate ions are gives as below‐ ClO 4 − + 2H + + 2e − → ClO 3 − + H 2 O; E o = 1 .19 V BrO 4 − + 2H + + 2e − → BrO 3 − + H 2 O; E o = 1 .74 V IO 4 − + 2H + + 2e − → IO 3 − + H 2 O; E o = +1 .65 V More the standard reduction potential, more is the tendency of perhalite ion to undergo reduction and stronger will be an oxidizing agent.