|
18 |
|
|
Atomic mass |
39.948 g.mol -1 |
|
Electronegativity according to Pauling |
unknown |
|
Density |
1.78.10 -3 g.cm -3 at 0 °C |
|
Melting point |
-189 °C |
|
Boiling point |
-185.7 °C |
|
Vanderwaals radius |
0.192 nm |
|
Ionic radius |
unknown |
|
Isotopes |
6 |
|
Electronis shell |
[Ne] 3s23p6 |
|
Energy of first ionisation |
1520 kJ.mol -1 |
| Energy of second ionisation | 2665.8 kJ.mol -1 |
| Energy of third ionisation | 3931 kJ.mol -1 |
|
Discovered by |
Sir Ramsay in 1894 |