Ruthenium

Symbol: Ru
Atomic number: 44
Category: transition metals
Group: 8
Period: 5
Block: d
Atomic weight: 101.07 g/mol
Electrons per shell: 2, 8, 18, 15, 1
CAS number: 7440-18-8
Phase: solid
Density: 12.45 kg/l (near room temperature)
Melting point: 2607 K (2334C, 4233F)
Boiling point: 4423 K (4150C, 7502F)
Crystal structure: hexagonal
Oxidation states: 8, 6, 4, 3, 2, 1
Electronegativity: 2.3 (Pauling scale)
Name's origin: Ruthenia
Name's meaning: the finder of this element, Karl Klaus, named the element after his birthland, which was at the time a part of the Russian empire (in Latin Ruthenia)
Facts:
- is found associated with platinum ores
- is used as a catalyst in some platinum alloys
- due to its ability to harden platinum and palladium, ruthenium is used in platinum and palladium alloys to make wear-resistant electrical contacts