Nickel Group: Elements of the Tenth Subgroup

This chapter describes the occurrences, manufacturing processes, properties, and applications of the elements of the tenth subgroup of the periodic table (nickel, palladium, platinum, and darmstadtium) and their important compounds. Nickel was discovered in 1751, palladium in 1803, and platinum, at least in alloy form, was already known in ancient Egypt. The first atoms of darmstadtium were produced in 1994. The impact of the lanthanide contraction can also be seen in the pair of elements palladium and platinum. The physical properties of these two elements differ significantly, but the chemical ones only slightly. The properties of nickel differ significantly from those of the two “noble” platinum metals palladium and platinum, as nickel shows a negative standard potential as well as lower densities, melting and boiling points. For nickel, the oxidation state +2 is the most stable, while palladium and platinum each occur with the oxidation states +2 and +4. Palladium and platinum are often used in catalysts, including those for cleaning car exhaust gases. Nickel is an essential component of corrosion-resistant steels.