Input interpretation
U-238 (uranium-238) | U-235 (uranium-235) | U-234 (uranium-234)
Natural abundance
U-238 | U-235 | U-234 99.2742% | 0.7204% | 0.0054%
Decay properties
| U-238 | U-235 | U-234 half-life | 4.47 Gyr (4.464 to 4.4745 Gyr) | 0.704 Gyr (702.2 to 706.6 Myr) | 0.2455 Myr (-4 to 4 Myr) mean lifetime | 6.45 Gyr (6.4453 to 6.4552 Gyr) | 1.02 Gyr (1.014 to 1.019 Gyr) | 0.3542 Myr (-8 to 8 Myr) decay constant | 4.916×10^-18 per second | 3.12×10^-17 per second | 8.953×10^-14 per second specific activity | 12.44 kBq/g | 79.8 kBq/g | 230.4 MBq/g width | 3.236×10^-33 eV | 2.05×10^-32 eV | 4.084×10^-29 eV decay modes | α (alpha emission) | SF (spontaneous fission) | 2β^- (double beta decay) | α (alpha emission) | SF (spontaneous fission) | ^28Mg (cluster emission) | ^25Ne (cluster emission) | ^20Ne (cluster emission) | α (alpha emission) | SF (spontaneous fission) | ^28Mg (cluster emission) | ^24Ne +^26Ne (double cluster emission) final decay products | Pb-206 (100%) | Tl-205 (1.9×10^-6%) | Pb-208 (2.6×10^-9%) | W-184 (9×10^-12%) | Yb-168 (5×10^-27%) | Er-164 (4×10^-27%) | Dy-160 (2×10^-28%) | Dy-156 (1×10^-30%) | Sm-144 (1×10^-31%) | Ce-140 (1×10^-32%) | Dy-164 (0%) | Er-168 (0%) | Gd-156 (0%) | Hf-176 (0%) | Hf-180 (0%) | Sm-152 (0%) | Yb-172 (0%) | Pb-207 (100%) | Tl-205 (9×10^-8%) | Pb-206 (8×10^-10%) | Pb-208 (1×10^-12%) | Pb-206 (100%) | Tl-205 (1.9×10^-6%) | Pb-208 (2.6×10^-9%) | W-184 (9×10^-12%) | Hf-180 (0%)
Biological properties
| U-235 biological half-life | 15 days biological lifetime | 22 days effective half-life | 15 days effective lifetime | 22 days
Decay modes
U-238
decay mode | α (alpha emission) branching ratio | 100% Q-value | 4.26975 MeV (megaelectronvolts) daughter nuclide | Th-234 decay mode | SF (spontaneous fission) branching ratio | 5.45×10^-5% decay mode | 2β^- (double beta decay) branching ratio | 2.2×10^-10% Q-value | 1.1442 MeV (megaelectronvolts) daughter nuclide | Pu-238
U-235
decay mode | α (alpha emission) branching ratio | 100% Q-value | 4.67826 MeV (megaelectronvolts) daughter nuclide | Th-231 decay mode | SF (spontaneous fission) branching ratio | 7×10^-9% decay mode | ^28Mg (cluster emission) branching ratio | 8×10^-10% daughter nuclide | Hg-207 decay mode | ^25Ne (cluster emission) branching ratio | 8×10^-10% daughter nuclide | Pb-210 decay mode | ^20Ne (cluster emission) branching ratio | 8×10^-10% daughter nuclide | Pb-215
U-234
decay mode | α (alpha emission) branching ratio | 100% Q-value | 4.85773 MeV (megaelectronvolts) daughter nuclide | Th-230 decay mode | SF (spontaneous fission) branching ratio | 1.73×10^-9% decay mode | ^28Mg (cluster emission) branching ratio | 1.4×10^-11% daughter nuclide | Hg-206 decay mode | ^24Ne +^26Ne (double cluster emission) branching ratio | 9×10^-12% daughter nuclide | Hf-184
Radiation shielding
| U-238 | U-235 | U-234 lead | 12.3 µm | 13.8 µm | 14.5 µm water | 29.8 µm | 34 µm | 36 µm air | 27.1 mm | 31 mm | 32.8 mm
Decay chain
U-238
Decay chain U-238
U-235
Decay chain U-235
U-234
Decay chain U-234
Mass properties
| atomic number (Z) | mass number (A) | neutron number U-238 | 92 | 238 | 146 U-235 | 92 | 235 | 143 U-234 | 92 | 234 | 142 | atomic mass | mass excess | binding energy per nucleon U-238 | 238.050788247 u (unified atomic mass units) | 47.308948 MeV (megaelectronvolts) | 7.57012 MeV (megaelectronvolts) U-235 | 235.043929918 u (unified atomic mass units) | 40.920456 MeV (megaelectronvolts) | 7.590907 MeV (megaelectronvolts) U-234 | 234.040952088 u (unified atomic mass units) | 38.146625 MeV (megaelectronvolts) | 7.600708 MeV (megaelectronvolts)
Mass properties