| Element | Helium | Symbol | He |
| Atomic Number | 2 | Molar Mass | 4 gmol-1 |
| Electron Configuration | 1s2 | Normal State | gas/nonmetal |
| Density @STP | 0.18x10-3 g cm-3 | Melting Point | -272oC |
| Boiling Point | -296oC | Stable Isotopes | 3He, 4He |
| Atomic Radius | 128 pm | Ionic Radius | n/a pm |
| Electronegativity (Pauling) | n/a | Ionization Energy (1st) | 2372 kJ mol-1 |
| Ionization Energy (2nd) | 5250 kJ mol-1 | Ionization Energy (3rd) | n/a kJ mol-1 |
| Molar Heat Capacity | 20.8 J K-1mol-1 | Standard Molar Entropy | 126.2 J K-1mol-1 |
| Enthalpy of Fusion | 0.021 kJ mol-1 | Enthalpy of Vapourization | 0.082 kJ mol-1 |