Krypton
Krypton (氪, symbol Kr) is chemical element number 36, a Noble Gas in period 4, group 18 of the periodic table, with a standard atomic weight of about 83.798. Colorless, odorless noble gas. Used in lasers, high-performance lighting, and flashes.
Properties
| Atomic number | 36 |
|---|---|
| Symbol | Kr |
| Atomic mass | 83.798 u |
| Category | Noble Gas |
| Period | 4 |
| Group | 18 |
| Electron configuration | [Ar] 3d¹⁰ 4s² 4p⁶ |
| Electronegativity | 3 |
| Covalent radius | 116 pm |
| Density | 0.003733 g/cm³ |
| Melting point | 115.79 K |
| Boiling point | 119.93 K |
| Discovery | Ramsay & Travers, 1898 |
Overview
Colorless, odorless noble gas. Used in lasers, high-performance lighting, and flashes. Krypton (symbol Kr) is chemical element number 36, sitting in period 4, group 18 of the periodic table and classed as a Noble Gas. As a noble gas it has a full outer shell, is extremely unreactive, and exists as a monatomic gas at room temperature.
It has the configuration [Ar] 3d¹⁰ 4s² 4p⁶ and an electronegativity near 3; its 8 outer-shell electrons drive its bonding. Under standard conditions it exists as a gas (a very low melting point); it melts near 115.79 K (-157.4 °C), boils near 119.93 K (-153.2 °C), has a density around 0.003733 g/cm³.
It is widely used in Industrial Gas. It was first described by Ramsay & Travers in 1898.
Electron shells
Electrons per shell: 2 · 8 · 18 · 8
Main uses
- Industrial Gas
Hazard
Compounds containing Krypton
No compounds in this knowledge base contain Krypton yet.
Data sources
Atomic mass uses IUPAC (CIAAW) standard atomic weights; the covalent radius is from Cordero et al. (2008). Verify on the RSC Periodic Table, PubChem and Wikipedia. Educational reference only.