Periodic Table


Atomic number: 10
Atomic weight: 20.1797
Symbol: Ne
Group number: 18
Electronic configuration: [He].2s2.2p6


It is a very inert element. Neon forms an unstable hydrate. In a vacuum discharge tube, neon glows reddish orange. Of all the rare gases, the discharge of neon is the most intense at ordinary voltages and currents. It is present in the atmosphere as 1 part in 65000. Liquid neon has over 40 times more refrigerating capacity than liquid helium, and more than 3 times that of liquid hydrogen.

General information

Discoveror: Sir William Ramsay, Morris W.Travers
Date discovered: 1898
Discovered at: London, England
Meaning of name: From the Greek word "neon" meaning "new"

Physical data

Standard state: gas at 298 K
Colour: colourless
Density of solid at ambient temperature/kg m-3: no data
Molar volume/cm3: 13.23

Radii /pm

Atomic: 38
Covalent (single bond):
Pauling radius for the ion [Ne]-: no data

Valence shell orbital radius maxima (Rmax)
orbital s p d f
radius36.133.6no datano data


Both values are quoted on the Pauling scale.

Pauling: no data
Allred Rochow: 4.84

Crystal Structure

structure: ccp (cubic close-packed)

The following CrystalMaker image represents the solid state structure. For most elements, the most stable allotrope is illustrated. Try WebElements version 2 for interactive virtual reality and CHIME images.


Temperatures (/K)

melting point: 24.56
boiling point: 27.07

Enthalpies /kJ mol-1

fusion: 0.34
vaporization: 1.74

single bond enthalpies:
Ne-F Ne-Cl Ne-Br Ne-I Ne-Ne
no data no data no data no data 3.93

Ionization enthalpies /kJ mol-1

Number Enthalpy


This section gives some data for naturally occurring isotopes.
Nominal mass Accurate mass % natural abundance
20Ne19.9924356 (22)90.48 (3)
21Ne20.9938428 (21)0.27 (1)
22Ne21.9913831 (18)9.25 (3)

Further Information

Copyright 1997 Mark Winter
Department of Chemistry at the University of Sheffield, Sheffield S3 7HF, England.

The current version of this document is at http://www.shef.ac.uk/~chem/web-elements-I/Ne.html