Helium-4
| General | |
|---|---|
| Symbol | 4He |
| Names | helium-4 |
| Protons (Z) | 2 |
| Neutrons (N) | 2 |
| Nuclide data | |
| Natural abundance | 99.999863% (atmosphere) |
| Half-life (t1/2) | stable |
| Isotope mass | 4.002603254 Da |
| Spin | 0 |
| Nuclear binding energy | 28295.7 keV |
| Isotopes of helium Complete table of nuclides | |
Helium-4 (4
He) is a stable isotope of the element helium. It is by far the more abundant of the two naturally occurring isotopes of helium, making up virtually all the helium on Earth. Its nucleus consists of two protons and two neutrons and is identical to an alpha particle.