Inorganic chemistry of these oxidation states

These share tendencies to behave as one-equivalent oxidants with redox potentials in the range 1.0 to 2.0 V and to undergo hydrolysis in aqueous solution above pH 2. They form complexes with anions, e.g. sulphate, which make their reactivity dependent on the nature of the medium both from the point of redox potential and of ligand displacement (Table 11). 

The segregation of these oxidants from Cu(II) and Fe(III) is based upon their much greater reactivity and their restriction to low pH. 

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