RUTENIUM

A polyvalent hard white metal, ruthenium is a member of the platinum group and is in group 8 of the periodic table: However, it has an atypical configuration in its outermost electron shells: whereas all other group 8 elements have 2 electrons in the outermost shell, in ruthenium, one of those is transferred to a lower shell. This effect can be observed in the neighboring metals niobium (41), rhodium (45), and palladium (46). Ruthenium has four crystal modifications and does not tarnish unless subject to high temperatures. Ruthenium dissolves in fused alkalis, is not attacked by acids but isattacked by halogens at high temperatures. Small amounts of ruthenium can increase the hardness of platinum and palladium. The corrosion resistance of titanium is increased markedly by the addition of a small amount of ruthenium. [5] The metal can be plated either by electroplating or by thermal decomposition methods. A ruthenium-molybdenum alloy is known to be superconductive at temperatures below 10.6 K.