Physics > Radioactive Isotopes
Each radioactive isotope has its own decay pattern. The rate at which an isotope decays is known as its half-life. The term half-life is defined as the time it takes for half of the atoms of a particular radioactive material to disintegrate. Half lives of radioactive isotopes vary greatly from milliseconds to thousands of millions of years.
| Radioisotope |
Half-life |
| BPolonium-215 |
0.0018 seconds |
| Bismuth-212 |
60.5 seconds |
| Sodium-24 |
15 hours |
| Iodine-131 |
8.07 days |
| Cobalt-60 |
5.26 years |
| Radium-226 |
1600 years |
| Uranium-238 |
4.5 billion years |