A group of three malleable ductile transition metals forming group 11 (formerly IB) of the periodic table: copper (Cu), silver (Ag), and gold (Au). Their outer electronic configurations have the form nd10(n+1)s1. Although this is similar to that of alkali metals, the coinage metals all have much higher ionization energies and higher (and positive) standard electrode potentials. Thus, they are much more difficult to oxidize and are more resistant to corrosion. In addition, the fact that they have d-electrons makes them show variable valency (CuI, CuII, and CuIII; AgI and AgII; AuI and AuIII) and form a wide range of coordination compounds. They are generally classified with the transition elements.
Subjects: Chemistry — Physics.