Kr           Krypton               36                     83.80(g)             18

Melting Point           Boiling Point          State @ Room Temp.

115.79 K    or            119.93 K  or          gas @ 298 K

Electron Configuration                Specific Heat                           

[Ar].3d¹⁰.4s².4p⁶                                       

History

In Great Britain, Krypton was discovered in 1898 by Sir William Ramsay and his student Morris W. Travers.  This element was left in the remains after boiling away water, oxygen, nitrogen, helium, and argon from a sample of air.  Krypton became present in the air at about 1 ppm.  Krypton comes from the Greek word 'kryptos" meaning "hidden".

Physical Description

Under normal conditions, Krypton is a colorless, odorless, and fairly expensive gas. This element is one of the noble gases. It is present in the air at about 1ppm.  This gas is characterized by brilliant green and orange spectral lines. As a solid, Krypton is a white crystalline substance.

Uses

Krypton can be used with argon as a low pressure filling gas for fluorescent lights. Krypton is also used in some photographic flash lamps for high-speed photography and lamps. Krypton emits a brigh, orange-red light in an electric-discharge tube; it is used in lightning airfields because the light is visible for long distances and pentrates fog and haze better than ordinary light