Ac
Actinium (Atomic Number 89)
Category: actinide | Period 7, Group 3 | Block: f
Soft, silvery radioactive metal giving name to actinide series.
Atomic & Physical Constants
- Standard Atomic Weight:
- 227 u
- Standard State Phase:
- Solid
- Electron Configuration:
- 2, 8, 18, 32, 18, 9, 2
- Electronegativity (Pauling):
- 1.1
- Melting Point:
- 1500 K
- Boiling Point:
- 3500 K
Historical Discovery & Real-World Applications
Industrial & Scientific Uses
Targeted alpha therapy (TAT) radio-immunotherapy cancer research
Discovery History
Discovered by Friedrich Oskar Giesel (1899).
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