36Kr83.798
Krypton (Kr)
Element 36 · Noble gas
Krypton (Kr) is a chemical element with atomic number 36. It is classified as a noble gas in period 4, group 18 of the periodic table (the p-block). Its standard atomic weight is 83.798 u and its ground-state electron configuration is [Ar] 3d¹⁰ 4s² 4p⁶.
Krypton facts
| Atomic number (Z) | 36 |
|---|---|
| Symbol | Kr |
| Standard atomic weight | 83.798 u |
| Category | Noble gas |
| Group | 18 |
| Period | 4 |
| Block | p-block |
| Electron configuration | [Ar] 3d¹⁰ 4s² 4p⁶ |
| Electronegativity (Pauling) | 3.0 |
| State at 20 °C | Gas |
| Protons / electrons | 36 / 36 |
| Neutrons (most common isotope, approx.) | 48 |
| Molar mass | 83.798 g/mol |