Element:	Neon
Symbol:	Ne
Atomic number:	10
Atomic weight:	20.1797(6)
Electron configuration:	1s2 2s2 2p6
Ground level:	1S0
Ionization potential:	21.5645 ev
Physical form:	Colorless gas
Melting point:	-248.6°C
Boiling point:	-246.053°C
Critical temperature:	-228.7°C
Density:	0.825 g/L
Specific heat:	1.030 J/g•K
Valence	0

Origin of name: Gr. neos, new

Discovered by Ramsay and Travers in 1898. Neon is a rare gaseous element present in the atmosphere to the extent of 1 part in 65,000. It is obtained by liquefaction of air and separated from the other gases by fractional distillation.

Natural neon is a mixture of three isotopes. Fourteen other unstable isotopes are known. It is very inert element, and it is still questionable if true compounds of neon exist. The following ions are known from optical and mass spectrometric studies: Ne⁺, (NeAr)⁺, (NeH)⁺, and (HeNe)⁺. Neon also 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. Neon is used in making the common neon advertising signs, which accounts for its largest use. It is also used to make high-voltage indicators, lightning arrestors, wave meter tubes, and TV tubes. Neon and helium are used in gas lasers. Liquid neon is now commercially available and is finding important application as an economical cryogenic refrigerant. It has over 40 times more refrigerating capacity per unit volume than liquid helium and more than three times that of liquid hydrogen. It is compact, inert, and is less expensive than helium when it meets refrigeration requirements.

Neon costs about $800/80 cu. ft. (2265 l).