Question

Among the 3d series, ___ has the highest stable oxidation state.

Answer 1

In this series, the 3d orbital is progressively being filled. The elements that have the greatest number of oxidation states are placed in or near the middle of the series. Particularly, Manganese exhibits all the oxidation states from +2 to +7, which is the highest exhibited in this series.

The number of stable oxidation states decreases as we move from the middle toward either extreme. In the early series, elements like Scandium and titanium have too few electrons to lose or share. On the other hand, elements like Copper and zinc have too many d electrons that fill the 3d orbitals to a greater extent.