Neon
Definition and meaning of Neon in chemistry.
![Neon element card: symbol Ne, atomic number 10, atomic mass 20.180, electron configuration [He] 2s² 2p⁶, Noble gas, group 18, period 2, gas at room temperature.](/assets/images/terms/neon-chemical-element.webp)
Neon is a chemical element with the symbol Ne and atomic number 10. It is a colorless, odorless, and completely inert monatomic gas.
In more detail
Neon is located in group 18 of the periodic table. It is the second-lightest noble gas after helium. Neon is a truly inert gas with a full octet of valence electrons.
This complete outer electron shell makes it highly unreactive. There are no known stable compounds of neon under standard laboratory conditions. It remains one of the least reactive elements in the universe.
Neon is the fifth most abundant element in the universe by mass. However, it is relatively scarce here on our home planet. Neon is very light and completely chemically inert.
These two traits allowed it to easily escape Earth's atmosphere. It floated away into space during the planet's initial formation. Today, companies extract commercial neon directly from the atmospheric air.
They do this by cooling the air until it becomes a liquid. Then they separate the individual gases using a process called fractional distillation. Neon boasts the narrowest liquid temperature range of any known element.
It melts into a liquid at a freezing -248.59 °C. It boils into a gas rapidly at -246.046 °C. Liquid neon has a much higher refrigerating capacity than liquid helium.
This special quality makes it a highly valuable cryogenic refrigerant. Scientists use it in specialized laboratory settings for extreme cooling tasks. When ionized inside a vacuum tube, neon atoms become highly excited. The excited neon atoms emit a brilliant, intense reddish-orange light.
Key facts
| Field | General Chemistry |
|---|---|
| Symbol | Ne |
| Atomic number | 10 |
| Atomic mass | 20.180 u |
| Category | Noble-Gas |
| State at room temperature | Gas |
| Melting point | -248.59 °C (-415.46 °F) |
The most famous application of neon is in luminous advertising signs. Manufacturers seal the low-pressure gas inside custom glass tubes. An electrical current flows through the tubes and excites the gas. This electrical reaction produces the classic bright reddish-orange glow.
Frequently asked questions
Are all brightly colored luminous signs filled with neon?
No, only signs that glow reddish-orange contain pure neon gas. Manufacturers produce other vibrant colors using different noble gases like argon or krypton. They can also coat the glass tubes with fluorescent phosphors.
Is neon dangerous to breathe in a natural environment?
Neon is chemically non-toxic. However, it acts as a simple asphyxiant. If a leak fills a confined space and displaces the oxygen, a person can suffer severe suffocation.
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Sources & references
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