Zinc Group: Elements of the Second Subgroup

The properties of the elements of the second subgroup (zinc, cadmium, mercury, copernicium) are relatively similar. Cadmium is intermediate in its properties between zinc and mercury. Zinc and cadmium have negative standard potentials and are thus base metals, whereas mercury is a semi-metal. The elements of this group usually give off one or two outer valence electrons to achieve a stable electron configuration. For zinc and cadmium, the oxidation states +2 are the most stable, for mercury +1 and +2. For the highest element of this subgroup, copernicium, hardly any chemical investigations have been carried out so far. It is expected to behave chemically similar to mercury. Zinc as an element has been known since the 17th century, cadmium since 1817, whereas mercury was already known in antiquity. The first successful production of copernicium atoms was achieved in 1996.