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Promethium

Lanthanide
Atomic Mass
(145) u
Density
7.26 g/cm³
Melting Point
1,104 °C
Boiling Point
3,000 °C
State
Solid
Discovery
1945

Discovery

Discovered by Jacob A. Marinsky, Lawrence E. Glendenin, and Charles D. Coryell in 1945 as a byproduct of uranium fission.

Common Uses

  • Used in nuclear batteries for spacecraft
  • Applied in luminous paints
  • Portable X-ray sources

Interesting Facts

  • Only lanthanide without stable isotopes
  • Byproduct of uranium fission
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