Krypton

Kr
CAS Number 7439-90-9
UN1056 (gas)
UN1970 (refrigerated liquid)

Molecule
Properties
Applications
Safety & Compatibility
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Liquid / Gas Volumes

Calculate the volume or mass of a quantity of gas or liquid

Liquid Phase

At boiling point at 1.013 bar

m³ (Volume)

kg (Mass)

Gas Phase

In standard conditions (1.013 bar, 15°C)

m³ (Volume)

kg (Mass)

Physical Properties

Download the set of data (XLS - 62.16 KB)

General Properties
Solid Phase
Liquid Phase
Gas Phase

Molecule phase diagram showing the transition phases between solid, liquid and gas as a function of temperature and pressure

Pressure (bar)

- Molar mass 83.798 g/mol
- Content in dry air 1.14 ppm
Critical Point
- Temperature -63.80 °C
- Pressure 55.0195 bar
- Density 918.86 kg/m³
Triple Point
- Temperature -157.38 °C
- Pressure 7.32E-1 bar

Pressure 1.013 bar

Latent heat of fusion (at melting point)	19.572 kJ/kg
Melting point	- 157.37 °C

Pressure 1.013 bar

Boiling point	- 153.42 °C
Latent heat of vaporization (at boiling point)	107.06 kJ/kg
Liquid density (at boiling point)	2416.7 kg/m³

Pressure 1.013 bar

0 °C
15 °C
25 °C

Compressibility factor Z	9.9725E-1
Cp/Cv ratio γ	1.6734
Gas density (at boiling point)	8.816 kg/m³
Gas density	3.748 kg/m³
Gas/(liquid at boiling point) equivalent	644.8 vol/vol
Heat capacity Cp	2.495E-1 kJ/(kg.K)
Heat capacity Cv	1.4911E-1 kJ/(kg.K)
Specific gravity	2.9
Specific volume	2.668E-1 m³/kg
Thermal conductivity	8.652 mW/(m.K)
Viscosity	2.3219E-4 Po

Compressibility factor Z	9.9768E-1
Cp/Cv ratio γ	1.6726
Gas density	3.5514 kg/m³
Gas/(liquid at boiling point) equivalent	680.49 vol/vol
Heat capacity Cp	2.4931E-1 kJ/(kg.K)
Heat capacity Cv	1.4905E-1 kJ/(kg.K)
Solubility in water	5.696E-5 mol/mol
Specific gravity	2.9
Specific volume	2.816E-1 m³/kg
Thermal conductivity	9.082 mW/(m.K)
Viscosity	2.4375E-4 Po

Compressibility factor Z	9.9793E-1
Cp/Cv ratio γ	1.6722
Gas density	3.4314 kg/m³
Gas/(liquid at boiling point) equivalent	704.29 vol/vol
Heat capacity Cp	2.492E-1 kJ/(kg.K)
Heat capacity Cv	1.4902E-1 kJ/(kg.K)
Solubility in water	4.512E-5 mol/mol
Specific gravity	2.9
Specific volume	2.914E-1 m³/kg
Thermal conductivity	9.363 mW/(m.K)
Viscosity	2.5132E-4 Po

Applications

Examples of uses of this molecule in Industry and Healthcare

Electronic components

Mixed with an halogen, Krypton is used for excimer lasers (laser with varying wavelength)

Glass

Krypton increases acoustic and thermal isolation performance of double-glazed windows.

Oil & Gas

Krypton is used instead of air to insulate offshore natural gas or oil piping systems

Photonics

Krypton is used to produce high-intensity, long-life lamps. It is used to fill halogen sealed-beam headlights.

Safety & Compatibility

Major Hazards
Material Compatibility

GHS04

Gas under pressure

Odor

none

Metals

Aluminium	Satisfactory
Brass	Satisfactory
Monel	No data
Copper	No data
Ferritic Steel	Satisfactory
Stainless steel	Satisfactory
Zinc	No data
Titanium	No data

Plastics

Polytetrafluoroethylene	Satisfactory
Polychlorotrifluoroethylene	Satisfactory
Polyvinylidene fluoride	Satisfactory
Polyvinyl chloride	Satisfactory
Ethylene tetrafluoroethylene	No data
Polycarbonate	No data
Polyamide	Satisfactory
Polypropylene	Satisfactory

Elastomers

Butyl (isobutene- isoprene) rubber	Satisfactory
Nitrile rubber	Satisfactory
Chloroprene	Satisfactory
Chlorofluorocarbons	No data
Silicone	Satisfactory
Perfluoroelastomers	Satisfactory
Fluoroelastomers	Satisfactory
Neoprene	No data
Polyurethane	Satisfactory
Ethylene-Propylene	Satisfactory

Lubricants

Hydrocarbon based lubricant	Satisfactory
Fluorocarbon based lubricant	Satisfactory

Materials compatibility

Recommendations : Air Liquide has gathered data on the compatibility of gases with materials to assist you in evaluating which materials to use for a gas system. Although the information has been compiled from what Air Liquide believes are reliable sources (International Standards: Compatibility of cylinder and valve materials with gas content; Part 1- Metallic materials: ISO11114-1 (March 2012), Part 2 - Non-metallic materials: ISO11114-2 (April 2013), it must be used with extreme caution and engineering judgement. No raw data such as these can cover all conditions of concentration, temperature, humidity, impurities and aeration. It is therefore recommended that this table is only used to identify possible materials for applications at high pressure and ambient temperature. Extensive investigation and testing under the specific conditions of use need to be carried out to validate a material selection for a given application. Contact the regional Air Liquide team for expertise service.

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More information

Krypton was discovered in 1898 by Sir William Ramsay and Moris William Travers. Its name comes from the Greek "κρυπτόν" (kryptos) meaning "hidden". Neon, krypton and xenon are known as "rare" gases, since combined they only account for one thousandth of the air which surrounds us. These gases are colorless and tasteless. They are so inert that they do not react and can only be combined with other chemical substances with great difficulty. Their extreme inertness makes them very valuable for certain applications.