Quick Facts
| Property | Value |
|---|---|
| Symbol | Ne |
| Atomic Number | 10 |
| Atomic Mass | 20.180 u |
| Category | Noble Gas |
| Period | 2 |
| Group | 18 |
| Block | p |
| Electron Configuration | [He] 2s² 2p⁶ |
Physical Properties
| Property | Value |
|---|---|
| State at 20°C | Gas |
| Density | 0.0009002 g/cm³ |
| Melting Point | -248.59°C (24.56 K) |
| Boiling Point | -246.08°C (27.07 K) |
| Appearance | Colorless gas (glows reddish-orange in discharge) |
Atomic Properties
| Property | Value |
|---|---|
| Electron Configuration | [He] 2s² 2p⁶ |
| Electronegativity | N/A (no stable compounds) |
| First Ionization Energy | 2080.7 kJ/mol |
| Atomic Radius | 38 pm |
| Covalent Radius | 58 pm |
| Van der Waals Radius | 154 pm |
History and Discovery
Discovered by: William Ramsay and Morris Travers Year of Discovery: 1898 Location: London, England
Etymology
The name "neon" comes from the Greek word "neos" meaning "new." William Ramsay's son suggested the name when the element was discovered.
Discovery Story
William Ramsay and Morris Travers discovered neon in 1898 while studying liquefied air. After discovering argon and helium, they suspected more noble gases existed. By evaporating liquid argon, they collected the first gas to boil off and found it had a unique spectrum with brilliant crimson light. They named it neon for its novelty.
Isotopes
| Isotope | Natural Abundance | Half-life | Decay Mode |
|---|---|---|---|
| ²⁰Ne | 90.48% | Stable | - |
| ²¹Ne | 0.27% | Stable | - |
| ²²Ne | 9.25% | Stable | - |
Occurrence
Natural Abundance
Neon is the fifth most abundant element in the universe but rare on Earth, making up only about 18.2 ppm of the atmosphere. It is formed by nucleosynthesis in stars. On Earth, it is primarily obtained as a byproduct of liquid air production.
Extraction and Production
- Fractional Distillation of Air: Neon is obtained from liquid air
- Byproduct: Produced during liquid oxygen and nitrogen manufacturing
- Production Volume: About 2,000 tons produced annually worldwide
- Relatively expensive due to low abundance
Applications and Uses
Lighting Applications
- Neon signs (produces characteristic reddish-orange glow)
- Indicator lights
- High-voltage indicators
- Advertising displays
Scientific Applications
- Cryogenic refrigeration (liquid neon)
- Laser medium (helium-neon lasers)
- Vacuum tubes
- Gas discharge tubes
Industrial Applications
- Lightning arresters
- Wavemeter tubes
- Television tubes (historically)
- High-voltage equipment
Other Uses
- Diving gas mixtures (deep diving)
- Plasma displays (though less common now)
Biological Role
Neon has no known biological role. It is chemically inert and does not participate in any biochemical processes.
In the Human Body
Neon is not used or processed by the body. When inhaled, it is simply exhaled unchanged.
Medical Uses
No significant medical applications, though it poses no toxicity risk.
Safety and Hazards
Toxicity
Neon is non-toxic but can act as a simple asphyxiant by displacing oxygen in enclosed spaces.
Handling Precautions
- Compressed gas cylinders require standard handling procedures
- Can cause asphyxiation in poorly ventilated areas
- Liquid neon can cause frostbite
- No fire hazard—completely inert
Environmental Impact
Neon is environmentally benign. It does not contribute to ozone depletion or climate change.
Interesting Facts
- Neon signs were first demonstrated publicly in Paris in 1910 by Georges Claude
- Despite the term "neon lights," many "neon" signs actually use other gases (argon gives blue, mercury gives white)
- Neon has over 40 times the refrigerating capacity of liquid helium
- Pure neon produces only a reddish-orange glow; other colors require different gases or phosphor coatings
- Neon is the second-lightest noble gas after helium