Krypton

<p>Krypton  is a <a href="/facts/Chemical_element/0jducgWD">chemical element</a>; it has <a href="/facts/Symbol_(chemistry)/2Fe1VAL0">symbol</a> Kr and <a href="/facts/Atomic_number/bgAr581S">atomic number</a> 36. It is a colorless, odorless <a href="/facts/Noble_gas/j0yHMEAE">noble gas</a> that occurs in <a href="/facts/Trace_element/fcIekKdo">trace amounts</a> in the <a href="/facts/Earth%2527s_atmosphere/FV97Am25">atmosphere</a> and is often used with other rare gases in <a href="/facts/Fluorescent_lamp/R8SlXCyg">fluorescent lamps</a>. Krypton is <a href="/facts/Chemically_inert/oglbxzgk">chemically inert</a>.
</p><p>Krypton, like the other noble gases, is used in lighting and <a href="/facts/Photography/ezLPT43M">photography</a>. Krypton light has many <a href="/facts/Spectral_line/HuI4Bj5f">spectral lines</a>, and krypton <a href="/facts/Plasma_(physics)/1d3btMVU">plasma</a> is useful in bright, high-powered gas lasers (krypton <a href="/facts/Ion_laser/Kd3jDNqk">ion</a> and <a href="/facts/Excimer_laser/Tw8UrIc7">excimer</a> lasers), each of which resonates and amplifies a single spectral line. <a href="/facts/Krypton_fluoride_laser/YLpst5cP">Krypton fluoride</a> also makes a useful <a href="/facts/Laser_medium/Gmcharyh">laser medium</a>. From 1960 to 1983, the <a href="/facts/History_of_the_metre/cR3xfvhn">official definition of the metre</a> was based on the <a href="/facts/Wavelength/kcJU0ymz">wavelength</a> of one spectral line of krypton-86, because of the high power and relative ease of operation of krypton <a href="/facts/Discharge_tube/uPNhhy7I">discharge tubes</a>.
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Krypton open-in-new

Krypton