Pm
Promethium
LanthanideAtomic Number: 61 • Atomic Mass: 145.0000 u • Period: 6 • Group: 101
Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f⁵
Phase: Solid
Electronegativity: 1.13
Occurrence
Promethium is found in various natural sources, including minerals, rocks, and the Earth's crust.
- Only trace amounts in uranium ores
- Made artificially in nuclear reactors