It's Elemental
Isotopes of the Element Thorium
Thorium
Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information.
Isotopes With A Known Natural Abundance
| Mass Number | Natural Abundance | Half-life |
| 232 | 100% | 1.40×1010 years |
Known Isotopes
| Mass Number | Half-life | Decay Mode | Branching Percentage |
| 208 | 1.7 milliseconds | Alpha Decay | 100.00% |
| 209 | 2.5 milliseconds | Alpha Decay | No Data Available |
| 210 | 16 milliseconds | Electron Capture | ~ 1.00% |
| Alpha Decay | 99.00% | ||
| 211 | 0.04 seconds | Alpha Decay | No Data Available |
| 212 | 31.7 milliseconds | Alpha Decay | 100.00% |
| Electron Capture | ~ 0.30% | ||
| 213 | 144 milliseconds | Alpha Decay | <= 100.00% |
| 214 | 87 milliseconds | Alpha Decay | 100.00% |
| 215 | 1.2 seconds | Alpha Decay | 100.00% |
| 216 | 26.0 milliseconds | Alpha Decay | 100.00% |
| Electron Capture | ~ 0.01% | ||
| 216m | 134 microseconds | Alpha Decay | 2.80% |
| Isomeric Transition | No Data Available | ||
| 217 | 0.241 milliseconds | Alpha Decay | 100.00% |
| 218 | 117 nanoseconds | Alpha Decay | 100.00% |
| 219 | 1.05 microseconds | Alpha Decay | 100.00% |
| 220 | 9.7 microseconds | Alpha Decay | 100.00% |
| Electron Capture | 2.0×10-7 % | ||
| 221 | 1.68 milliseconds | Alpha Decay | 100.00% |
| 222 | 2.8 milliseconds | Alpha Decay | 100.00% |
| 223 | 0.60 seconds | Alpha Decay | 100.00% |
| 224 | 0.81 seconds | Alpha Decay | 100.00% |
| 225 | 8.75 minutes | Electron Capture | ~ 10.00% |
| Alpha Decay | ~ 90.00% | ||
| 226 | 30.57 minutes | Alpha Decay | 100.00% |
| 227 | 18.68 days | Alpha Decay | 100.00% |
| 228 | 1.9116 years | Alpha Decay | 100.00% |
| Emission of an oxygen-20 nucleus | 1×10-11 % | ||
| 229 | 7932 years | Alpha Decay | 100.00% |
| 229m | 2 minutes | Isomeric Transition (suspected) | No Data Available |
| 230 | 7.54×10+4 years | Alpha Decay | 100.00% |
| Emission of a neon-24 nucleus | 6×10-11 % | ||
| Spontaneous Fission | <= 4×10-12 % | ||
| 231 | 25.52 hours | Alpha Decay | ~ 4×10-11 % |
| Beta-minus Decay | 100.00% | ||
| 232 | 1.40×1010 years | Alpha Decay | 100.00% |
| Spontaneous Fission | 1.1×10-9 % | ||
| 233 | 21.83 minutes | Beta-minus Decay | 100.00% |
| 234 | 24.10 days | Beta-minus Decay | 100.00% |
| 235 | 7.2 minutes | Beta-minus Decay | 100.00% |
| 236 | 37.3 minutes | Beta-minus Decay | 100.00% |
| 237 | 4.7 minutes | Beta-minus Decay | 100.00% |
| 238 | 9.4 minutes | Beta-minus Decay | 100.00% |
| 239 | No Data Available | No Data Available | No Data Available |
Citation and linking information
For questions about this page, please contact Carol McKisson.