Reed Relays and
Electronics India Limited
Manufacturer of Reed Switches, Reed Sensors and Reed-based products
Reed Relays and Electronics India Limited Incorporated in 1971
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Ruthenium

Ruthenium is a chemical element with the symbol Ru and atomic number 44. It is a hard silvery-white metal of the transition series. Because of its high melting point and excellent wear resistance, the use as plating or sputtering material in reed switches is preferred.

Ruthenium (Wikipedia)

Ruthenium,  44Ru
Ruthenium a half bar.jpg
General properties
Pronunciation /rˈθniəm/ (roo-THEE-nee-əm)
Appearance silvery white metallic
Standard atomic weight (Ar, standard) 101.07(2)
Ruthenium in the periodic table
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 Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver 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 Gold Mercury (element) Thallium Lead 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 Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
Fe

Ru

Os
technetiumrutheniumrhodium
Atomic number (Z) 44
Group group 8
Period period 5
Element category   transition metal
Block d-block
Electron configuration [Kr] 4d7 5s1
Electrons per shell
2, 8, 18, 15, 1
Physical properties
Melting point 2607 K ​(2334 °C, ​4233 °F)
Boiling point 4423 K ​(4150 °C, ​7502 °F)
Density (near r.t.) 12.45 g/cm3
when liquid (at m.p.) 10.65 g/cm3
Heat of fusion 38.59 kJ/mol
Heat of vaporization 619 kJ/mol
Molar heat capacity 24.06 J/(mol·K)
Vapor pressure
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, 1, 2, 3, 4, 5, 6, 7, 8 ​(a mildly acidic oxide)
Electronegativity Pauling scale: 2.2
Ionization energies
  • 1st: 710.2 kJ/mol
  • 2nd: 1620 kJ/mol
  • 3rd: 2747 kJ/mol
Atomic radius empirical: 134 pm
Covalent radius 146±7 pm
Color lines in a spectral range
Miscellanea
Crystal structurehexagonal close-packed (hcp)
Hexagonal close packed crystal structure for ruthenium
Speed of sound 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 nΩ·m (at 0 °C)
Magnetic ordering paramagnetic
Magnetic susceptibility +43.2·10−6 cm3/mol (298 K)
Young's modulus 447 GPa
Shear modulus 173 GPa
Bulk modulus 220 GPa
Poisson ratio 0.30
Mohs hardness 6.5
Brinell hardness 2160 MPa
CAS Number 7440-18-8
History
Naming after Ruthenia (Latin for: medieval Kyivska Rus' region)
Discovery and first isolation Karl Ernst Claus (1844)
Main isotopes of ruthenium
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
96Ru 5.54% stable
97Ru syn 2.9 d ε 97Tc
γ
98Ru 1.87% stable
99Ru 12.76% stable
100Ru 12.60% stable
101Ru 17.06% stable
102Ru 31.55% stable
103Ru syn 39.26 d β 103Rh
γ
104Ru 18.62% stable
106Ru syn 373.59 d β 106Rh
| references | in Wikidata

Ruthenium 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. The Russian-born scientist of Baltic-German ancestry and a member of the Russian Academy of Science Karl Ernst Claus discovered the element in 1844 at Kazan State University in Russia and named it after the Latin name of his homeland, Ruthenia. Ruthenium is usually found as a minor component of platinum ores; the annual production is about 20 tonnes. Most ruthenium produced is used in wear-resistant electrical contacts and thick-film resistors. A minor application for ruthenium is in platinum alloys and as a chemistry catalyst. A new application of ruthenium is as the capping layer for extreme ultraviolet photomasks. Ruthenium is generally found in ores with the other platinum group metals in the Ural Mountains and in North and South America. Small but commercially important quantities are also found in pentlandite extracted from Sudbury, Ontario and in pyroxenite deposits in South Africa.

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