Ruthenium

Ruthenium is a chemical element wi seembol Ru an atomic nummer 44. It is a rare transeetion metal belangin the platinum group o the periodic table. Lik the ither metals o the platinum group, ruthenium is inert tae maist ither chemicals. The Baltic German scientist Karl Ernst Claus diskivered the element in 1844, an named it efter Ruthenia, the Laitin wird for Rus'. Ruthenium uisually occurs as a minor component o platinum ores; annual production is aboot 20 tonne. Maist ruthenium produced is uised for wear-resistant electrical contacts an the production o thick-film resistors. A minor application o ruthenium is its uise in some platinum alloys.

Ruthenium, ₄₄Ru

Ruthenium
Pronunciation	/ruːˈθiːniəm/ ​(roo-THEE-nee-əm)
Appearance	sillery white metallic
Standard atomic weight Ar, std(Ru)	7002101070000000000♠101.07(2)
Ruthenium in the periodic cairt
Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Airn Cobalt Nickel Capper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Siller (element) Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gowd Mercur (element) Thallium Leid (element) Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Ununtrium Flerovium Ununpentium Livermorium Ununseptium Ununoctium Fe ↑ Ru ↓ Os technetium ← ruthenium → rhodium
Atomic nummer (Z)	44
Group	group 8
Period	period 5
Block	d-block
Element category	Transeetion metal
Electron confeeguration	[Kr] 4d7 5s1
Electrons per shell	2, 8, 18, 15, 1
Pheesical properties
Phase at STP	solit
Meltin pynt	2607 K ​(2334 °C, ​4233 °F)
Bylin pynt	4423 K ​(4150 °C, ​7502 °F)
Density (near r.t.)	12.45 g/cm3
when liquid (at m.p.)	10.65 g/cm3
Heat o fusion	38.59 kJ/mol
Heat o vapourisation	591.6 kJ/mol
Molar heat capacity	24.06 J/(mol·K)
Vapour pressur P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 2588 2811 3087 3424 3845 4388
Atomic properties
Oxidation states	−4, −2, 0, +1, +2, +3, +4, +5, +6, +7, +8 (a mildly acidic oxide)
Electronegativity	Pauling scale: 2.2
Atomic radius	empirical: 134 pm
Covalent radius	146±7 pm
Colour lines in a spectral range Spectral lines o ruthenium
Ither properties
Naitural occurrence	primordial
Creestal structur	​hexagonal close-packed (hcp)
Speed o soond thin rod	5970 m/s (at 20 °C)
Thermal expansion	6.4 µm/(m·K) (at 25 °C)
Thermal conductivity	117 W/(m·K)
Electrical resistivity	71 n Ω·m (at 0 °C)
Magnetic orderin	paramagnetic
Young's modulus	447 GPa
Shear modulus	173 GPa
Bulk modulus	220 GPa
Poisson ratio	0.30
Mohs haurdness	6.5
Brinell haurdness	2160 MPa
CAS Nummer	7440-18-8
History
Diskivery	Jędrzej Śniadecki (1807)
First isolation	Jędrzej Śniadecki (1807)
Recognised as a distinct element by	Karl Ernst Claus (1844)
Main isotopes o ruthenium
Iso­tope Abun­dance Hauf-life (t1/2) Decay mode Pro­duct 96Ru 5.52% >6.7×1016 y (β+β+) 96Mo 97Ru syn 2.9 d ε 97Tc γ - 98Ru 1.88% - (SF) - 99Ru 12.7% - (SF) - 100Ru 12.6% - (SF) - 101Ru 17.0% - (SF) - 102Ru 31.6% - (SF) - 103Ru syn 39.26 d β− 103Rh γ - 104Ru 18.7% - (β−β−) 104Pd 106Ru syn 373.59 d β− 106Rh
Decay modes in parentheses is predict, but hisna yet been observed