Rhenium

  • rhenium, 75re
    rhenium single crystal bar and 1cm3 cube.jpg
    rhenium
    pronunciationm/ (ree-nee-əm)
    appearancesilvery-grayish
    standard atomic weight ar, std(re)186.207(1)[1]
    rhenium 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
    tc

    re

    bh
    tungstenrheniumosmium
    atomic number (z)75
    groupgroup 7
    periodperiod 6
    blockd-block
    element category  transition metal
    electron configuration[xe] 4f14 5d5 6s2
    electrons per shell2, 8, 18, 32, 13, 2
    physical properties
    phase at stpsolid
    melting point3459 k ​(3186 °c, ​5767 °f)
    boiling point5903 k ​(5630 °c, ​10,170 °f)
    density (near r.t.)21.02 g/cm3
    when liquid (at m.p.)18.9 g/cm3
    heat of fusion60.43 kj/mol
    heat of vaporization704 kj/mol
    molar heat capacity25.48 j/(mol·k)
    vapor pressure
    p (pa) 1 10 100 1 k 10 k 100 k
    at t (k) 3303 3614 4009 4500 5127 5954
    atomic properties
    oxidation states−3, −1, 0, +1, +2, +3, +4, +5, +6, +7 (a mildly acidic oxide)
    electronegativitypauling scale: 1.9
    ionization energies
    • 1st: 760 kj/mol
    • 2nd: 1260 kj/mol
    • 3rd: 2510 kj/mol
    • (more)
    atomic radiusempirical: 137 pm
    covalent radius151±7 pm
    color lines in a spectral range
    spectral lines of rhenium
    other properties
    natural occurrenceprimordial
    crystal structurehexagonal close-packed (hcp)
    hexagonal close packed crystal structure for rhenium
    speed of sound thin rod4700 m/s (at 20 °c)
    thermal expansion6.2 µm/(m·k)
    thermal conductivity48.0 w/(m·k)
    electrical resistivity193 nΩ·m (at 20 °c)
    magnetic orderingparamagnetic[2]
    magnetic susceptibility+67.6·10−6 cm3/mol (293 k)[3]
    young's modulus463 gpa
    shear modulus178 gpa
    bulk modulus370 gpa
    poisson ratio0.30
    mohs hardness7.0
    vickers hardness1350–7850 mpa
    brinell hardness1320–2500 mpa
    cas number7440-15-5
    history
    namingafter the river rhine (german: rhein)
    discoverymasataka ogawa (1908)
    first isolationmasataka ogawa (1919)
    named bywalter noddack, ida noddack, otto berg (1925)
    main isotopes of rhenium
    iso­tope abun­dance half-life (t1/2) decay mode pro­duct
    185re 37.4% stable
    187re 62.6% 4.12×1010 y β 187os
    category category: rhenium
    | references

    rhenium is a chemical element with the symbol re and atomic number 75. it is a silvery-gray, heavy, third-row transition metal in group 7 of the periodic table. with an estimated average concentration of 1 part per billion (ppb), rhenium is one of the rarest elements in the earth's crust. rhenium has the third-highest melting point and second-highest boiling point of any stable element at 5903 k.[4] rhenium resembles manganese and technetium chemically and is mainly obtained as a by-product of the extraction and refinement of molybdenum and copper ores. rhenium shows in its compounds a wide variety of oxidation states ranging from −1 to +7.

    discovered in 1908, rhenium was the second-last stable element to be discovered (the last being hafnium). it was named after the river rhine in europe.

    nickel-based superalloys of rhenium are used in the combustion chambers, turbine blades, and exhaust nozzles of jet engines. these alloys contain up to 6% rhenium, making jet engine construction the largest single use for the element. the second-most important use is as a catalyst: rhenium is an excellent catalyst for hydrogenation and isomerization, and is used for example in catalytic reforming of naphtha for use in gasoline (rheniforming process). because of the low availability relative to demand, rhenium is expensive, with price reaching an all-time high in 2008/2009 of us$10,600 per kilogram (us$4,800 per pound). due to increases in rhenium recycling and a drop in demand for rhenium in catalysts, the price of rhenium has dropped to us$2,844 per kilogram (us$1,290 per pound) as of july 2018.[5]

  • history
  • characteristics
  • production
  • applications
  • precautions
  • references
  • external links

Rhenium, 75Re
Rhenium single crystal bar and 1cm3 cube.jpg
Rhenium
Pronunciationm/ (REE-nee-əm)
Appearancesilvery-grayish
Standard atomic weight Ar, std(Re)186.207(1)[1]
Rhenium 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
Tc

Re

Bh
tungstenrheniumosmium
Atomic number (Z)75
Groupgroup 7
Periodperiod 6
Blockd-block
Element category  Transition metal
Electron configuration[Xe] 4f14 5d5 6s2
Electrons per shell2, 8, 18, 32, 13, 2
Physical properties
Phase at STPsolid
Melting point3459 K ​(3186 °C, ​5767 °F)
Boiling point5903 K ​(5630 °C, ​10,170 °F)
Density (near r.t.)21.02 g/cm3
when liquid (at m.p.)18.9 g/cm3
Heat of fusion60.43 kJ/mol
Heat of vaporization704 kJ/mol
Molar heat capacity25.48 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 3303 3614 4009 4500 5127 5954
Atomic properties
Oxidation states−3, −1, 0, +1, +2, +3, +4, +5, +6, +7 (a mildly acidic oxide)
ElectronegativityPauling scale: 1.9
Ionization energies
  • 1st: 760 kJ/mol
  • 2nd: 1260 kJ/mol
  • 3rd: 2510 kJ/mol
  • (more)
Atomic radiusempirical: 137 pm
Covalent radius151±7 pm
Color lines in a spectral range
Spectral lines of rhenium
Other properties
Natural occurrenceprimordial
Crystal structurehexagonal close-packed (hcp)
Hexagonal close packed crystal structure for rhenium
Speed of sound thin rod4700 m/s (at 20 °C)
Thermal expansion6.2 µm/(m·K)
Thermal conductivity48.0 W/(m·K)
Electrical resistivity193 nΩ·m (at 20 °C)
Magnetic orderingparamagnetic[2]
Magnetic susceptibility+67.6·10−6 cm3/mol (293 K)[3]
Young's modulus463 GPa
Shear modulus178 GPa
Bulk modulus370 GPa
Poisson ratio0.30
Mohs hardness7.0
Vickers hardness1350–7850 MPa
Brinell hardness1320–2500 MPa
CAS Number7440-15-5
History
Namingafter the river Rhine (German: Rhein)
DiscoveryMasataka Ogawa (1908)
First isolationMasataka Ogawa (1919)
Named byWalter Noddack, Ida Noddack, Otto Berg (1925)
Main isotopes of rhenium
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
185Re 37.4% stable
187Re 62.6% 4.12×1010 y β 187Os
Category Category: Rhenium
| references

Rhenium is a chemical element with the symbol Re and atomic number 75. It is a silvery-gray, heavy, third-row transition metal in group 7 of the periodic table. With an estimated average concentration of 1 part per billion (ppb), rhenium is one of the rarest elements in the Earth's crust. Rhenium has the third-highest melting point and second-highest boiling point of any stable element at 5903 K.[4] Rhenium resembles manganese and technetium chemically and is mainly obtained as a by-product of the extraction and refinement of molybdenum and copper ores. Rhenium shows in its compounds a wide variety of oxidation states ranging from −1 to +7.

Discovered in 1908, rhenium was the second-last stable element to be discovered (the last being hafnium). It was named after the river Rhine in Europe.

Nickel-based superalloys of rhenium are used in the combustion chambers, turbine blades, and exhaust nozzles of jet engines. These alloys contain up to 6% rhenium, making jet engine construction the largest single use for the element. The second-most important use is as a catalyst: rhenium is an excellent catalyst for hydrogenation and isomerization, and is used for example in catalytic reforming of naphtha for use in gasoline (rheniforming process). Because of the low availability relative to demand, rhenium is expensive, with price reaching an all-time high in 2008/2009 of US$10,600 per kilogram (US$4,800 per pound). Due to increases in rhenium recycling and a drop in demand for rhenium in catalysts, the price of rhenium has dropped to US$2,844 per kilogram (US$1,290 per pound) as of July 2018.[5]