Rare Gases are the most inert and unreactive elements known to man. They are found in very low concentrations in the environment (0.001818% neon, 0.000114% krypton and 0.0000087% xenon) and are manufactured by Air Separation Units (ASU).

Neon

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 par.

Neon is present to a small extent in the atmosphere and is obtained as a byproduct from the liquefaction and separation of air. This would not normally be carried out in the laboratory and neon is available commercially in cylinders under pressure.

Neon is used in making neon advertising signs, which accounts for its largest use. Used to make high-voltage indicators, lightning arrestors, wave meter tubes, and TV tubes. Neon and helium are used in making gas lasers.

Liquid neon is 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 less expensive than helium.

Qualitative performance

Product Denomination Standard articles Impurities, no more Total impurities,
no more
Neon Ne 5.0 UHP Ne < 99.999 vol.% He < 5 ppm < 10 ppm
  - N2 < 2 ppm - - -
- H2 < 1 ppm - - -
- O2 < 1 ppm - - -
- THC < 0.5 ppm - - -
- CO < 1 ppm - - -
- CO2 < - - - - -
- H2O < 0.5 ppm - - -
Neon Ne 5.5 UHP Kr > 99.9985 vol.% He < 1 ppm < 5 ppm
  - N2 < 1 ppm - - -
- H2 < 0.5 ppm - - -
- O2 < 0.3 ppm - - -
- THC < 0.3 ppm - - -
- CO < 0.1 ppm - - -
- CO2 - 0.1 ppm - - -
- H2O < 0.5 ppm - - -
Neon Liquide Ne 4.85 L Kr > 99.9985 vol.% He < 8 ppm < 15 ppm
  - N2 < 2 ppm - - -
- H2 < 1 ppm - - -
- O2 < 1 ppm - - -
- THC < 0.5 ppm - - -
- CO < 1 ppm - - -
- CO2 - - - - - -
- H2O < 1 ppm - - -
CAS NO. 7440-01-9
Molecular Weight 20.180
Phase at STP Gas
Apperance Colourless with orange-red glow under electric field
Odour Odourless
Taste Tasteless
Category Compressed Gas

Krypton

Liquid neon is 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 less expensive than helium.

Under normal conditions krypton is colourless, odourless, fairly expensive gas. Solid krypton is a white crystalline substance with a face-centered cubic structure which is common to all the "rare gases". Krypton difluoride, KrF2.

Krypton is present to a small extent (about 1 ppm by volume) in the atmosphere and is obtained as a byproduct from the liquefaction and separation of air. This would not normally be carried out in the laboratory and krypton is available commercially in cylinder.

Application

It used with argon as a low-pressure filling gas for fluorescent lights.It used in some photographic flash lamps for high-speed photography, lamps, UV-laser spectral line used for international measurement of a metre.

Product Denomination Standard articles Impurities, no more Total impurities,
no more
Krypton Kr 5.0 UHP Kr > 99.999 vol.% Xe < 3 ppm < 10 ppm
  - N2 < 3 ppm - - -
- Ar < 1 ppm - - -
- H2 < 0.1 ppm - - -
- O2 < 1 ppm - - -
- CF < 0.1 ppm - - -
- THC < 0.5 ppm - - -
- CO < 0.5 ppm - - -
- CO2 - - - - - -
- H2O < 1 ppm - - -
Krypton Kr 5.5 UHP Kr > 99.9995 vol.% Xe < 1 ppm < 5 ppm
  - N2 < 1 ppm - - -
- Ar < 1 ppm - - -
- H2 < 0.1 ppm - - -
- O2 < 0.3 ppm - - -
- CF < 0.1 ppm - - -
- THC < 0.1 ppm - - -
- CO < 0.1 ppm - - -
- CO2 < 0.1 ppm - - -
- H2O < 0.5 ppm - - -
Krypton Kr 6.0 RG Kr > 99.9999 vol.% Xe < 0.3 ppm < 1 ppm
  - N2 < 0.1 ppm - - -
- Ar < 0.1 ppm - - -
- H2 < 0.1 ppm - - -
- O2 < 0.1 ppm - - -
- CF < 0.1 ppm - - -
- THC < 0.1 ppm - - -
- CO < 0.1 ppm - - -
- CO2 < 0.1 ppm - - -
- H2O < 0.1 ppm - - -

Technical Specifications

CAS NO. 7439-90-9
Molecular Weight 83.80
Phase at STP Gas
Apperance Colourless with white glow under electric field
Odour Odourless
Taste Tasteless
Category Compressed Gas

Xenon

Xenon is a "noble" or "inert" gas present in the atmosphere to a small extent. Xenon is present in the Martian atmosphere to the extent of about 0.08 ppm. Before 1962, it was generally assumed that xenon and other noble gases were unable to form compounds.

Metallic xenon is produced by applying several hundred kilobars of pressure. Xenon in a vacuum tube produces a blue glow when excited by an electrical discharge and finds use in strobe lamps. It is an odourless, colourless, inert gas.

Xenon is present to a small extent in the atmosphere (less than 1 ppm by volume) and is obtained as a byproduct from the liquefaction and separation of air. This would not normally be carried out in the laboratory and xenon is available commercially.

Applications

Xenon is present to a small extent in the atmosphere (less than 1 ppm by volume) and is obtained as a byproduct from the liquefaction and separation of air. This would not normally be carried out in the laboratory and xenon is available commercially.

Product Denomination Standard articles Impurities, no more Total impurities,
no more
Xenon Xe 5.0 UHP Xe > 99.999 vol.% Kr < 3 ppm < 10 ppm
  - N2 < 3 ppm - - -
- Ar < 1 ppm - - -
- H2 < 0.1 ppm - - -
- O2 < 1 ppm - - -
- CF < 0.1 ppm - - -
- THC < 0.5 ppm - - -
- CO < 0.5 ppm - - -
- CO2 - - - - - -
- H2O < 1 ppm - - -
Xenon Xe 5.0 UHP Xe > 99.9999 vol.% Kr < 3 ppm < 10 ppm
  - N2 < 3 ppm - - -
- Ar < 1 ppm - - -
- H2 < 0.1 ppm - - -
- O2 < 1 ppm - - -
- CF < 0.1 ppm - - -
- THC < 0.5 ppm - - -
- CO < 0.5 ppm - - -
- CO2 - - - - - -
- H2O < 1 ppm - - -
Xenon Xe 6.0 RG Xe > 99.9999 vol.% Kr < 1 ppm < 1 ppm
  - N2 < 0.3 ppm - - -
- Ar < 0.1 ppm - - -
- H2 < 0.1 ppm - - -
- O2 < 0.1 ppm - - -
- CF < 0.1 ppm - - -
- THC < 0.1 ppm - - -
- CO < 0.1 ppm - - -
- CO2 - 0.1 ppm - - -
- H2O < 0.1 ppm - - -
CAS NO. 7440-63-3
Molecular Weight 131.29
Phase at STP Gas
Apperance Colourless with blue glow under electric field
Odour Odourless
Taste Tasteless
Category Compressed Gas