Th
Thorium (Atomic Number 90)
Category: actinide | Period 7, Group 3 | Block: f
Naturally occurring radioactive actinide 3x more abundant than uranium.
Atomic & Physical Constants
- Standard Atomic Weight:
- 232.03774 u
- Standard State Phase:
- Solid
- Electron Configuration:
- 2, 8, 18, 32, 18, 10, 2
- Electronegativity (Pauling):
- 1.3
- Melting Point:
- 2023 K
- Boiling Point:
- 5061 K
Historical Discovery & Real-World Applications
Industrial & Scientific Uses
Thorium nuclear fuel cycles, high-temperature gas mantle filaments
Discovery History
Discovered by Jöns Jakob Berzelius (1828).
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