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  • Elements

    KRYPTON
    36
    Kr
    83.798 (2) g m


    Name: kryptonGroup number: 18
    Symbol: KrGroup name: Noble gas
    Atomic number: 36Period number: 4
    Atomic weight: 83.798 (2) g mBlock: p-block
    CAS Registry ID: 7439-90-9Voice:
    Standard state: gas at 298 KColour: colourless
    Classification: Non-metallicAvailability:

    krypton
    Image adapted with permission from Prof James Marshall"s (U. North Texas, USA) Walking Tour of the elements CD.

    Krypton is present in the air at about 1 ppm. The atmosphere of Mars contains a little (about 0.3 ppm) of krypton. It is characterised by its brilliant green and orange spectral lines. The spectral lines of krypton are easily produced and some are very sharp. In 1960 it was internationally agreed that the fundamental unit of length, the metre, should be defined as 1 m = 1,650,763.73 wavelengths (in vacuo) of the orange-red line of Kr-33.

    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, has been prepared in gram quantities and can be made by several methods.

    Isolation

    Here is a brief summary of the isolation of krypton.

    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 cylinders at high pressure.

    Fluorides
  • KrF2
  • Chlorides
    none listed
    Bromides
    none listed
    Iodides
    none listed
    Hydrides
    none listed
    Oxides
    none listed
    Sulfides
    none listed
    Selenides
    none listed
    Tellurides
    none listed
    Nitrides
    none listed






    Our data and resources are taken from Web Elements