Element 36
Krypton
Noble gases
Krypton (Kr) is in the p-block of the periodic table — group 18, period 4.
Krypton (from Greek:κρυπτός kryptos "the hidden one") is a chemical element with symbol Kr and atomic number 36.
Key data
- Atomic number
- 36
- Atomic mass
- 83.798 u
- Group / Period
- 18 / 4
- Block
- p-block
- Phase at STP
- Gas
- Density
- 3.749 g/cm³
- Melting point
- -157.4 °C
- Boiling point
- -153.2 °C
- Electron configuration
- [Ar] 3d10 4s2 4p6
Periodic table block
Krypton is in the p-block (group 18, period 4). Elements land in the p-block when their highest-energy electrons fill a p subshell — this region holds most nonmetals, the metalloids, and the metals on the right of the table.
New to this? Periodic table blocks explained: s, p, d, and f
Common uses
- •High-end light bulbs
- •Lasers
- •Window insulation
Discovery
Year: 1898
Discovered by: William Ramsay
Frequently asked questions
What is the atomic number of Krypton?
Krypton has atomic number 36. Its symbol is Kr and its atomic mass is 83.798 u.
What category of element is Krypton?
Krypton is classified as noble gases. It sits in group 18, period 4 of the periodic table.
What block of the periodic table is Krypton in?
Krypton is in the p-block (group 18, period 4). Its highest-energy electrons occupy the p subshell — you can see this in its electron configuration, [Ar] 3d10 4s2 4p6.
What is Krypton used for?
Common uses of Krypton include: High-end light bulbs, Lasers, Window insulation.
When was Krypton discovered?
Krypton was discovered in 1898 by William Ramsay.
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