Ar
Argon (Atomic Number 18)
Category: noble | Period 3, Group 18 | Block: p
Inert shield gas; third most abundant in atmosphere.
Atomic & Physical Constants
- Standard Atomic Weight:
- 39.9481 u
- Standard State Phase:
- Gas
- Electron Configuration:
- 2, 8, 8
- Electronegativity (Pauling):
- N/A
- Melting Point:
- 83.81 K
- Boiling Point:
- 87.302 K
Historical Discovery & Real-World Applications
Industrial & Scientific Uses
TIG welding shield, double-pane window insulation, lighting
Discovery History
Discovered by Lord Rayleigh (1894).
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