Tantalum-158
Properties and data of the isotope 158Ta.
See also: List of individual Tantalum isotopes (and general data sources).
General data
Name of the isotope:Tantalum-158; Ta-158Symbol:158Ta or 15873TaMass number A:158 (= number of nucleons)Atomic number Z:73 (= number of protons)Neutrons N:85Isotopic mass:157.96654(21) u (atomic weight of Tantalum-158)Nuclide mass:157.9264976 u (calculated nuclear mass without electrons)Mass excess:-31.16779 MeVMass defect:1.341205196 u (per nucleus)Nuclear binding energy:1249.32459284 MeV (per nucleus)
7.90711768 MeV (average binding energy per nucleon)Separation energy:SN = 9.64(25) MeV (first neutron)Half-life:55(15) msDecay constant λ:12.602676010181 s-1Specific activity α:4.834082174869 × 10+22 Bq g-1
1306508695910.7 Ci g-1Spin and parity:
(nuclear angular momentum)(2-)Year of discovery:1979
Radioactive Decay
Half-life T½ = 55(15) ms respectively 5.5 × 10-2 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| α | 154Lu | 91 % | 6.124(4) MeV | |
| EC/β+ | 158Hf | 9 % | 10.94(20) MeV | |
Parent Nuclides
Direct parent isotope is: 162Re.
Nuclear Isomers
Nuclear isomers or excited states with the activation energy in keV related to the ground state.
| Nuclear Isomer | Excitation Energy | Half-life | Spin |
|---|
| 158mTa | 141(9) keV | 36.7(15) ms | (9+) |
| 158m2Ta | 2805.55(4) keV | 6.1(1) μs | (19-) |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 85) and isobaric (same nucleon number A = 158) with Tantalum-158. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 85 | Isobar A = 158 |
|---|
| 47 | 132Ag | |
| 48 | 133Cd | |
| 49 | 134In | |
| 50 | 135Sn | |
| 51 | 136Sb | |
| 52 | 137Te | |
| 53 | 138I | |
| 54 | 139Xe | |
| 55 | 140Cs | |
| 56 | 141Ba | |
| 57 | 142La | |
| 58 | 143Ce | 158Ce |
| 59 | 144Pr | 158Pr |
| 60 | 145Nd | 158Nd |
| 61 | 146Pm | 158Pm |
| 62 | 147Sm | 158Sm |
| 63 | 148Eu | 158Eu |
| 64 | 149Gd | 158Gd |
| 65 | 150Tb | 158Tb |
| 66 | 151Dy | 158Dy |
| 67 | 152Ho | 158Ho |
| 68 | 153Er | 158Er |
| 69 | 154Tm | 158Tm |
| 70 | 155Yb | 158Yb |
| 71 | 156Lu | 158Lu |
| 72 | 157Hf | 158Hf |
| 73 | 158Ta | 158Ta |
| 74 | 159W | 158W |
| 75 | 160Re | |
| 76 | 161Os | |
External data and identifiers
Last update: 2020-10-20
Perma link: https://www.chemlin.org/isotope/tantalum-158
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