Krypton

�(Kr), � chemical element, rare gas of Group 0 (noble gases) of the periodic table, forming very few chemical compounds. About three times heavier than air, krypton gas is colourless, odourless, and tasteless. Although traces are present in meteorites and minerals, krypton is more plentiful in the Earth's atmosphere, which contains 1 part krypton in about 900,000. The element was discovered