Attribute | Krypton × | Francium × |
---|---|---|
Standard state | Gas | Solid |
Electron affinity (eV) | - | 0.47 |
Electron configuration | [Ar]4s²3d¹⁰4p⁶ | [Rn]7s¹ |
Atomic mass (u) | 83.8 | 223.01973 |
Electronegativity (pauling scale) | 3 | 0.7 |
1↑Oxidation states |
|
|
Ionization energy (eV) | 14 | 3.9 |
Atomic radius (van der waals) (pm) | 202 | 348 |
Boiling point (K) | 119.93 | - |
Melting point (K) | 115.79 | 300 |
Density (g/cm³) | 0.003733 | - |
Atomic number | 36 | 87 |
Group name | Noble gas | Alkali metal |
Symbol | Kr | Fr |
Discovered (year) | 1898 | 1939 |