Se
Selenium (Atomic Number 34)
Category: reactive-nonmetal | Period 4, Group 16 | Block: p
Photoconductive nonmetal whose conductivity increases in light.
Atomic & Physical Constants
- Standard Atomic Weight:
- 78.9718 u
- Standard State Phase:
- Solid
- Electron Configuration:
- 2, 8, 18, 6
- Electronegativity (Pauling):
- 2.55
- Melting Point:
- 494 K
- Boiling Point:
- 958 K
Historical Discovery & Real-World Applications
Industrial & Scientific Uses
Photocells, solar cells, glass decolorizing, shampoo
Discovery History
Discovered by Jöns Jakob Berzelius (1817).
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