Praseodymium-138
Properties and data of the isotope 138Pr.
See also: List of individual Praseodymium isotopes (and general data sources).
General data
Name of the isotope:Praseodymium-138; Pr-138Symbol:138Pr or 13859PrMass number A:138 (= number of nucleons)Atomic number Z:59 (= number of protons)Neutrons N:79Nucleon pairing (Z - N):odd - oddNuclear ratio (N/Z ratio):1.3389830508475 (= neutron-proton ratio)Neutron excess (N-Z):20Isotopic mass:137.910752(12) u (atomic weight of Praseodymium-138)Nuclide mass:137.8783882 u (calculated nuclear mass without electrons)Mass excess:-83.13398 MeVMass defect:1.235453252 u (per nucleus)Nuclear binding energy:1150.81729152 MeV (per nucleus)
8.33925574 MeV (average binding energy per nucleon)Separation energy:SN = 8.004(14) MeV (first neutron)
SP = 4.504(11) MeV (first proton)Half-life:1.45(5) minDecay constant λ:0.0079672089719534 s-1Specific activity α:3.502164575887 × 10+19 Bq g-1
946530966.456 Ci g-1Spin and parity:
(nuclear angular momentum)1+Year of discovery:1951
Radioactive Decay
Half-life T½ = 1.45(5) min (minutes) respectively 8.7 × 101 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| EC/β+ | 138Ce | 100 % | 4.437(12) MeV | |
Parent Nuclides
Direct parent isotope is: 138Nd.
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 |
|---|
| 138mPr | 364(23) keV | 2.03(2) h | 7- |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 79) and isobaric (same nucleon number A = 138) with Praseodymium-138. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 79 | Isobar A = 138 |
|---|
| 44 | 123Ru | |
| 45 | 124Rh | |
| 46 | 125Pd | |
| 47 | 126Ag | |
| 48 | 127Cd | |
| 49 | 128In | |
| 50 | 129Sn | 138Sn |
| 51 | 130Sb | 138Sb |
| 52 | 131Te | 138Te |
| 53 | 132I | 138I |
| 54 | 133Xe | 138Xe |
| 55 | 134Cs | 138Cs |
| 56 | 135Ba | 138Ba |
| 57 | 136La | 138La |
| 58 | 137Ce | 138Ce |
| 59 | 138Pr | 138Pr |
| 60 | 139Nd | 138Nd |
| 61 | 140Pm | 138Pm |
| 62 | 141Sm | 138Sm |
| 63 | 142Eu | 138Eu |
| 64 | 143Gd | 138Gd |
| 65 | 144Tb | 138Tb |
| 66 | 145Dy | 138Dy |
| 67 | 146Ho | |
| 68 | 147Er | |
| 69 | 148Tm | |
| 70 | 149Yb | |
| 71 | 150Lu | |
External data and identifiers
Last update: 2020-10-19
Perma link: https://www.chemlin.org/isotope/praseodymium-138
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