Question

why do transition metals show variable oxidation states

Answer 1

Unpaired Electrons of d-orbitals. ... This is because unpaired valence electrons are unstable and eager to bond with other chemical species. This means that the oxidation states would be the highest in the very middle of the transition metal periods due to the presence of the highest number of unpaired valence electron

Answer 2

Hey !!

The valence electron of transition metals are in (n-1)d and ns orbital. As there is almost little energy difference between orbitals, both the energy levels can be used for bond formation. Thus, they exhibit variable oxidation states.

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