Neon is a rare element, making up only 0.001% of our atmosphere. Part of this percentage was lodged in the rocks of the Earth when the planet was formed, and was released into the air by volcanic eruptions. Pure neon is a transparent gas, which is extracted by cooling the air to a temperature of -189.34 °C (-189.34 °F). This element can be mixed with helium to create research lasers. However, it is more commonly used in lighting, such as in illuminated signs or as bright warning beacons on airport runways.

Summary of properties (Ne)

Atomic weight20.1797(6)
Discoverer (year)Ramsay, William & Travers, Morris (1898)
Natural formgas
Electron configuration[He] 2s2 2p6
Melting point (ºC)-249
Boiling point (ºC)-246
Abundance in earth's crust (ppm)0.005
Isotope (abundance)20Ne (90.48), 21Ne (0.27), 22Ne (9.25)
Density g/cm30.9
Van der Waals radius (pm)154
Covalent radius (pm)62
Electronegativity (Pauling)
Vaporization enthalpy (kJ/mol)1.71
Enthalpy of fusion (kJ/mol)0.33
Specific heat capacity (J/g·K) at 25ºC and 1 atm1.03
Thermal conductivity (W/cm·K) at 25ºC and 1 atm<0.001
Oxidation state0
Electron affinity (eV)unstable ion
1st Ionization potential (eV)21.5645

Back to the Periodic Table of the Elements.