Hydrogen |
| Symbol | H |
|---|---|
| Latin name | Hydrogenium |
| Atomic number | 1 |
| Period | 1 |
| Element category | Nonmetals |
| Relative atomic mass | 1.00794 |
| Group | I.A |
| Electronegativity | 2.1 |
| Oxidation numbers | -1, 1 |
| Electron configuration | 1s1 |
| Density [g/cm3] | 0.00008988 |
| State | Gas |
| Melting point [°C] | -259.34 |
| Boiling point [°C] | -252.87 |
| Critical point [°C] | -240.18 |
| Critical pressure [MPa] | 1.293 |
| Atomic radius [pm] | 53 |
| Covalent radius [pm] | 37 |
| Thermal conductivity [W m-1K-1] | 0.1815 |
| Heat capacity [J K-1g-1] | 14.304 |
| Discovery | 1766 |
| Stable isotopes | 2 |
| Unstable isotopes | 1 |