ELEMENTLE

Element 10 · Noble Gas

Neon

Period 2 · Group 18

Neon is a chemical element with symbol Ne and atomic number 10. It is in group 18 (noble gases) of the periodic table. Neon is a colorless, odorless, inert monatomic gas under standard conditions, with about two-thirds the density of air.

Three reasons Neon stands out

  1. 1

    Produces a distinctive red-orange glow.

  2. 2

    It is the fifth most abundant element in the entire universe.

  3. 3

    Despite its fame in signs, it was only discovered on Earth in 1898.

The true color of a neon sign

Excited neon atoms emit an unmistakable red-orange light. Many signs casually called “neon” use other gases or phosphor coatings for different colors, but genuine neon needs no such disguise. The element was separated from liquefied air in 1898, revealing a rare earthly gas with a bright electrical signature.

Neon at a glance
Atomic number / protons10
SymbolNe
Family (Elementle)Noble Gas
Classification (PubChem)Noble gas
Period2
Group18
Atomic mass (u)20.180
Standard stateGas
Electron configuration[He]2s2 2p6
Reported oxidation states0
Electronegativity (Pauling)Not available
Atomic radius (pm)154
First ionization energy (eV)21.565
Electron affinity (eV)Not available
Density (g/cm³)0.0008999
Melting point24.56 K (-248.59 °C)
Boiling point27.07 K (-246.08 °C)
Discovery (PubChem)1898

Values are reference data, not a specification for every temperature, pressure, or allotrope. Unknown properties are left unavailable. Superheavy-element predictions remain uncertain.

Sources & further reading

PubChem: Neon · Neon on Wikipedia

The introduction and original editorial story are adapted from Wikipedia contributors via Periodic-Table-JSON. Element descriptions and their adaptations are available under CC BY-SA 3.0. Numerical attributes use the PubChem periodic-table dataset, retrieved September 22, 2026.