Ruthenium

Symbol	Ru
Atomic number	44
Group	8 (Iron group)
Period	5
Block	d
Classification	Transition Metal

Appearance	Silvery white metallic
Color	Silver

Number of protons	44 p+
Number of neutrons	57 n0
Number of electrons	44 e-

From Wikipedia, the free encyclopediaRuthenium is a chemical element with symbol Ru and atomic number 44. It is a rare transition metal belonging to the platinum group of the periodic table. Like the other metals of the platinum group, ruthenium is inert to most other chemicals.

Phase at STP	Solid
Density	12.45 g/cm3
Atomic weight	101.072 u

Melting point	2607 K 2333.85 °C 4232.93 °F
Boiling point	4423 K 4149.85 °C 7501.73 °F
Heat of vaporization	567.77 kJ/mol

Electronegativity (Pauling Scale)	2.2
Electron affinity	100.96 kJ/mol
Oxidation states	−4, −2, 0, +1, +2, +3, +4, +5, +6, +7, +8 (a mildly acidic oxide)
Ionization energies	710.2 kJ/mol 1620 kJ/mol 2747 kJ/mol

Electron configuration Shorthand configuration	[Kr] 4d7 5s1
Electron configuration Full configuration	1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d7 5s1
Electron configuration chart	1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d7 5s1
Electrons per shell	2, 8, 18, 15, 1
Outer shell electrons	1
Valence electrons (incl. d)	8
Valency electrons	3
Bohr model	Figure: Shell diagram of Ruthenium (Ru) atom.
Orbital Diagram	1s 2s 2p 3s 3p 3d 4s 4p 4d 5s

Discovery and first isolation

Karl Ernst Claus (1844)

Discovery of ruthenium Though naturally occurring platinum alloys containing all six platinum-group metals were used for a long time by pre-Columbian Americans and known as a material to European chemists from the mid-16th century, not until the mid-18th century was platinum identified as a pure element. That natural platinum contained palladium, rhodium, osmium and iridium was discovered in the first decade of the 19th century. It is possible that the Polish chemist Jędrzej Śniadecki isolated element 44 (which he called "vestium" after the asteroid Vesta discovered shortly before) from South American platinum ores in 1807. He published an announcement of his discovery in 1808. His work was never confirmed, however, and he later withdrew his claim of discovery. Jöns Berzelius and Gottfried Osann nearly discovered ruthenium in 1827. They examined residues that were left after dissolving crude platinum from the Ural Mountains in aqua regia. Berzelius did not find any unusual metals, but Osann thought he found three new metals, which he called pluranium, ruthenium, and polinium. This discrepancy led to a long-standing controversy between Berzelius and Osann about the composition of the residues. As Osann was not able to repeat his isolation of ruthenium, he eventually relinquished his claims. In 1844, Karl Ernst Claus, a Russian scientist of Baltic German descent, showed that the compounds prepared by Gottfried Osann contained small amounts of ruthenium, which Claus had discovered the same year. Claus isolated ruthenium from the platinum residues of rouble production while he was working in Kazan University, Kazan. Choosing the name for the new element, Claus stated: "I named the new body, in honour of my Motherland, ruthenium. I had every right to call it by this name because Mr. Osann relinquished his ruthenium and the word does not yet exist in chemistry." In doing so, Claus started a trend that continues to this day - naming an element after a country.

Original word	Ruthenia
Language of origin	Latin
Name source	Place
Meaning	“Russia”
Country	Russia
Naming The name is derived from 'Ruthenia', the Latin name for Russia, as the platinum ores were originally from the Ural Mountains in Russia.

CAS Number	7440-18-8
ChemSpider ID	22390
EC number	231-127-1
PubChem CID Number	23950