Tl
Thallium (Atomic Number 81)
Category: post-transition | Period 6, Group 13 | Block: p
Extremely toxic, soft post-transition metal.
Atomic & Physical Constants
- Standard Atomic Weight:
- 204.38 u
- Standard State Phase:
- Solid
- Electron Configuration:
- 2, 8, 18, 32, 18, 3
- Electronegativity (Pauling):
- 1.62
- Melting Point:
- 577 K
- Boiling Point:
- 1746 K
Historical Discovery & Real-World Applications
Industrial & Scientific Uses
Infrared optical lenses, cardiac isotope stress imaging
Discovery History
Discovered by William Crookes (1861).
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