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Kr

Krypton

Atomic number: 36Mass: 83.798 uCategory: Noble Gas

About Krypton

Krypton is a colourless, odourless noble gas that occurs in trace amounts in the atmosphere. Its name comes from the Greek 'kryptos' meaning hidden. Krypton is used in some types of photographic flashes and fluorescent lights.

Properties

Period
4
Group
18
Block
P
Category
Noble Gas
Electronegativity
N/A
Ionization Energy
1350.8 kJ/mol
Melting Point
116 K (-157°C)
Boiling Point
120 K (-153°C)
Density
3.733 g/L
Oxidation States
+2

Electron Configuration

1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶
[Ar] 3d¹⁰ 4s² 4p⁶
Shell 1:2e⁻
Shell 2:8e⁻
Shell 3:18e⁻
Shell 4:8e⁻

Real-World Uses

Fluorescent lighting
Photography flashes
Laser technology
Insulating windows
KrF lasers

Fun Fact

Superman's weakness, Kryptonite, is named after real krypton — though the real element certainly won't hurt you!