Zinc, Cadmium and Mercury Group IIB

The /-transition metals are located between Groups HA and IflA in the periodic table. Strictly speaking, a /-transition metal must have a partially filled set of d orbitals. Zinc, cadmium, and mercury (Group IIB) and their cations have completely filled sets of d orbitals, but they are often discussed with /-transition metals because their properties are similar. All of the other elements in this region have partially filled sets of d orbitals, except the IB elements and palladium, which have completely filled sets. Some of the cations of these latter elements have partially filled sets of d orbitals. 

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