Fermium

Fermium ( /ˈfɜrmiəm/ FUR-mee-əm) is a synthetic element with the symbol Fm. It is the 100th element in the periodic table and a member of the actinide series. It is the heaviest element that can be formed by neutron bombardment of lighter elements, and hence the last element that can be prepared in macroscopic quantities, although pure fermium metal has not yet been prepared. A total of 19 isotopes are known, with Fm being the longest-lived one w... More

Atomic number:

  • 100

Periodic table block:

Van der Waals radius:

  • 200 pm (0.00000787 )

Chemical Element

The 100th Element in the Periodic Table

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Einsteinium

Einsteinium ( /aɪnˈstaɪniəm/ eyen-STY-nee-əm) is a synthetic element with the symbol Es and atomic number 99. It is the seventh transuranic element,...

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Mendelevium

Mendelevium ( /ˌmɛndəˈlɛviəm/ or /ˌmɛndəˈliːviəm/) is a synthetic element with the symbol Md (formerly Mv) and the atomic number 101. A metallic...

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Symbol:

  • Fm

Atomic mass:

  • 257 u (4.27E-16 µg )

Electrons per shell:

  • 2,8,18,32,30,8,2

Electronegativity (Pauling scale):

  • 1.3

Melting Point:

  • 1,526.85 °C (2780.36 °F )

Ionization Energy:

  • 6.5 eV (0.0000065 MeV )

Discovery Date:

  • 1953

Electron Configuration:

  • Rn 5f12 7s2
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