Krypton

Noble gas · atomic number 36

3683.7982KrKryptonGasNoble gas

Krypton (from Greek:κρυπτός kryptos "the hidden one") is a chemical element with symbol Kr and atomic number 36. It is a member of group 18 (noble gases) elements. A colorless, odorless, tasteless noble gas, krypton occurs in trace amounts in the atmosphere, is isolated by fractionally distilling liquefied air, and is often used with other rare gases in fluorescent lamps.

Properties of Krypton

Element category	Noble gas
Atomic number	36
Atomic mass	83.7982 u
Phase at STP	Gas
Group	18
Period	4
Block	p
Electron configuration	[Ar] 3d10 4s2 4p6
Electrons per shell	2, 8, 18, 8
Electronegativity (Pauling)	3
Melting point	115.78 K (-157 °C)
Boiling point	119.93 K (-153 °C)
Density	3.749 g/L
Discovered by	William Ramsay

← Bromine · Periodic table · Rubidium → Rb

About the noble gas group

Full outer electron shells make these gases almost inert: they barely react, glow in discharge lamps and are used to create unreactive atmospheres.

Data: Periodic-Table-JSON (CC BY-SA 3.0) · stored statically on our server. https://en.wikipedia.org/wiki/Krypton

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6 elements: Full outer electron shells make these gases almost inert: they barely react, glow in discharge lamps and are used to create unreactive atmospheres.

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