Fermium is a synthetic element wi seembol Fm an atomic nummer 100.

Fermium, 100Fm
Fermium
Pronunciation/ˈfɜːrmiəm/ (FUR-mee-əm)
Mass number[257]
Fermium 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
Er

Fm

(Upb)
einsteiniumfermiummendelevium
Atomic nummer (Z)100
Groupgroup n/a
Periodperiod 7
Blockf-block
Element category  Actinide
Electron confeeguration[Rn] 5f12 7s2
Electrons per shell2, 8, 18, 32, 30, 8, 2
Pheesical properties
Phase at STPsolit (predictit)
Meltin pynt1800 K ​(1527 °C, ​2781 °F) (predictit)
Atomic properties
Oxidation states+2, +3
ElectronegativityPauling scale: 1.3
Ionisation energies
  • 1st: 627 kJ/mol
  • (estimatit)
Ither properties
Naitural occurrencesynthetic
CAS Nummer7440-72-4
History
Naminefter Enrico Fermi
DiskiveryLawrence Berkeley Naitional Laboratory (1952)
Main isotopes o fermium
Iso­tope Abun­dance Hauf-life (t1/2) Decay mode Pro­duct
252Fm syn 25.39 h SF
α 248Cf
253Fm syn 3 d ε 253Es
α 249Cf
255Fm syn 20.07 h SF
α 251Cf
257Fm syn 100.5 d α 253Cf
SF
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