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100Fm

Element 100

Fermium

Actinides

Fermium is a synthetic element with symbol Fm and atomic number 100.

Key data

Atomic number
100
Atomic mass
257.000 u
Group / Period
3 / 7
Block
f-block
Phase at STP
Solid
Density
Melting point
1526.8 °C
Boiling point
Electron configuration
[Rn] 5f12 7s2

Common uses

  • Research only
  • Very short half-life
  • Synthesized post-WWII

Discovery

Year: 1953

Discovered by: Lawrence Berkeley National Laboratory

Frequently asked questions

What is the atomic number of Fermium?

Fermium has atomic number 100. Its symbol is Fm and its atomic mass is 257 u.

What category of element is Fermium?

Fermium is classified as actinides. It sits in group 3, period 7 of the periodic table.

What is Fermium used for?

Common uses of Fermium include: Research only, Very short half-life, Synthesized post-WWII.

When was Fermium discovered?

Fermium was discovered in 1953 by Lawrence Berkeley National Laboratory.

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