Neon
Element 10 · Noble Gas
Neon is famous for one thing: light. Run electricity through a tube of low-pressure neon and it blazes orange-red, the classic glow of advertising signs. Chemically, neon is famously lazy — its full outer shell gives it no reason to gain, lose, or share electrons, so it forms no stable compounds. It is the fifth most abundant element in the universe yet scarce on Earth, recovered by distilling liquid air. Beyond signs, neon fills high-voltage indicators, helium-neon lasers, and cryogenic cooling systems.
Key facts
| Atomic number | 10 |
|---|---|
| Atomic weight | 20.180 |
| Category | Noble Gas |
| Group / Period | 18 / 2 |
| Block | p |
| Electron configuration | 1s2 2s2 2p6 |
| Common oxidation states | 0 |
| State at STP | Gas |
| Atomic radius | 38 pm |
| Density | 0.00090 g/cm³ |
| Melting point | -248.59 °C |
| Boiling point | -246.05 °C |
Occurrence
Neon is a trace gas in air — about 18 parts per million — extracted by fractional distillation of liquefied air. Stars forge it in abundance, but Earth's gravity was too weak to hold much of it.
Applications
Neon signs and displays
Helium-neon lasers
High-voltage indicator lamps
Cryogenic refrigeration
Lightning arresters
Common compounds
- No stable compounds (noble gas)
Neon is the fifth most abundant element in the universe, but on Earth it is scarce — most of it escaped to space long ago.
Data source: IUPAC standard atomic weights 2021