La
Lanthanum
LanthanideAtomic Number: 57 • Atomic Mass: 138.9100 u • Period: 6 • Group: 3
Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 5d¹
Phase: Solid
Electronegativity: 1.1
Occurrence
Lanthanum is found in various natural sources, including minerals, rocks, and the Earth's crust.
- Earth's crust (30 parts per million)
- Monazite sand
- Bastnäsite mineral