Meitnerium

  • meitnerium, 109mt
    meitnerium
    pronunciation
    • m/[1]
      (neer-ee-əm)
    • m/[2]
      (myt-nər-ee-əm)
    mass number[278] (unconfirmed: 282)
    meitnerium 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
    ir

    mt

    (uht)
    hassiummeitneriumdarmstadtium
    atomic number (z)109
    groupgroup 9
    periodperiod 7
    blockd-block
    element category  unknown chemical properties, but probably a transition metal[3][4]
    electron configuration[rn] 5f14 6d7 7s2 (predicted)[3][5]
    electrons per shell2, 8, 18, 32, 32, 15, 2 (predicted)
    physical properties
    phase at stpsolid (predicted)[4]
    density (near r.t.)37.4 g/cm3 (predicted)[3]
    atomic properties
    oxidation states(+1), (+3), (+4), (+6), (+8), (+9) (predicted)[3][6][7][8]
    ionization energies
    • 1st: 800 kj/mol
    • 2nd: 1820 kj/mol
    • 3rd: 2900 kj/mol
    • (more) (all estimated)[3]
    atomic radiusempirical: 128 pm (predicted)[3][8]
    covalent radius129 pm (estimated)[9]
    other properties
    natural occurrencesynthetic
    crystal structureface-centered cubic (fcc)
    face-centered cubic crystal structure for meitnerium

    (predicted)[4]
    magnetic orderingparamagnetic (predicted)[10]
    cas number54038-01-6
    history
    namingafter lise meitner
    discoverygesellschaft für schwerionenforschung (1982)
    main isotopes of meitnerium
    iso­tope abun­dance half-life (t1/2) decay mode pro­duct
    274mt syn 0.4 s α 270bh
    276mt syn 0.6 s α 272bh
    278mt syn 4 s α 274bh
    282mt[11] syn 67 s? α 278bh
    category category: meitnerium
    | references

    meitnerium is a synthetic chemical element with the symbol mt and atomic number 109. it is an extremely radioactive synthetic element (an element not found in nature, but can be created in a laboratory). the most stable known isotope, meitnerium-278, has a half-life of 4.5 seconds, although the unconfirmed meitnerium-282 may have a longer half-life of 67 seconds. the gsi helmholtz centre for heavy ion research near darmstadt, germany, first created this element in 1982. it is named after lise meitner.

    in the periodic table, meitnerium is a d-block transactinide element. it is a member of the 7th period and is placed in the group 9 elements, although no chemical experiments have yet been carried out to confirm that it behaves as the heavier homologue to iridium in group 9 as the seventh member of the 6d series of transition metals. meitnerium is calculated to have similar properties to its lighter homologues, cobalt, rhodium, and iridium.

  • history
  • isotopes
  • predicted properties
  • experimental chemistry
  • notes
  • references
  • external links

Meitnerium, 109Mt
Meitnerium
Pronunciation
Mass number[278] (unconfirmed: 282)
Meitnerium 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
Ir

Mt

(Uht)
hassiummeitneriumdarmstadtium
Atomic number (Z)109
Groupgroup 9
Periodperiod 7
Blockd-block
Element category  Unknown chemical properties, but probably a transition metal[3][4]
Electron configuration[Rn] 5f14 6d7 7s2 (predicted)[3][5]
Electrons per shell2, 8, 18, 32, 32, 15, 2 (predicted)
Physical properties
Phase at STPsolid (predicted)[4]
Density (near r.t.)37.4 g/cm3 (predicted)[3]
Atomic properties
Oxidation states(+1), (+3), (+4), (+6), (+8), (+9) (predicted)[3][6][7][8]
Ionization energies
  • 1st: 800 kJ/mol
  • 2nd: 1820 kJ/mol
  • 3rd: 2900 kJ/mol
  • (more) (all estimated)[3]
Atomic radiusempirical: 128 pm (predicted)[3][8]
Covalent radius129 pm (estimated)[9]
Other properties
Natural occurrencesynthetic
Crystal structureface-centered cubic (fcc)
Face-centered cubic crystal structure for meitnerium

(predicted)[4]
Magnetic orderingparamagnetic (predicted)[10]
CAS Number54038-01-6
History
Namingafter Lise Meitner
DiscoveryGesellschaft für Schwerionenforschung (1982)
Main isotopes of meitnerium
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
274Mt syn 0.4 s α 270Bh
276Mt syn 0.6 s α 272Bh
278Mt syn 4 s α 274Bh
282Mt[11] syn 67 s? α 278Bh
Category Category: Meitnerium
| references

Meitnerium is a synthetic chemical element with the symbol Mt and atomic number 109. It is an extremely radioactive synthetic element (an element not found in nature, but can be created in a laboratory). The most stable known isotope, meitnerium-278, has a half-life of 4.5 seconds, although the unconfirmed meitnerium-282 may have a longer half-life of 67 seconds. The GSI Helmholtz Centre for Heavy Ion Research near Darmstadt, Germany, first created this element in 1982. It is named after Lise Meitner.

In the periodic table, meitnerium is a d-block transactinide element. It is a member of the 7th period and is placed in the group 9 elements, although no chemical experiments have yet been carried out to confirm that it behaves as the heavier homologue to iridium in group 9 as the seventh member of the 6d series of transition metals. Meitnerium is calculated to have similar properties to its lighter homologues, cobalt, rhodium, and iridium.