Attribute | Francium × | Argon × |
---|---|---|
Electron affinity (eV) | 0.47 | - |
Electronegativity (pauling scale) | 0.7 | - |
Atomic mass (u) | 223.01973 | 39.9 |
Standard state | Solid | Gas |
Oxidation states |
|
|
Electron configuration | [Rn]7s¹ | [Ne]3s²3p⁶ |
Ionization energy (eV) | 3.9 | 15.76 |
Atomic radius (van der waals) (pm) | 348 | 188 |
Boiling point (K) | - | 87.3 |
Melting point (K) | 300 | 83.8 |
Density (g/cm³) | - | 0.0017837 |
Atomic number | 87 | 18 |
Group name | Alkali metal | Noble gas |
Discovered (year) | 1939 | 1894 |
Symbol | Fr | Ar |