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Iodine (Atomic Number 53)
Category: halogen | Period 5, Group 17 | Block: p
Lustrous purple-black solid halogen that sublimes into deep violet gas.
Atomic & Physical Constants
- Standard Atomic Weight:
- 126.904473 u
- Standard State Phase:
- Solid
- Electron Configuration:
- 2, 8, 18, 18, 7
- Electronegativity (Pauling):
- 2.66
- Melting Point:
- 386.85 K
- Boiling Point:
- 457.4 K
Historical Discovery & Real-World Applications
Industrial & Scientific Uses
Thyroid health (iodized salt), medical antiseptics, X-ray contrast
Discovery History
Discovered by Bernard Courtois (1811).
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