Xenon-125
Properties and data of the isotope 125Xe.
See also: List of individual Xenon isotopes (and general data sources).
General data
Name of the isotope:Xenon-125; Xe-125Symbol:125Xe or 12554XeMass number A:125 (= number of nucleons)Atomic number Z:54 (= number of protons)Neutrons N:71Isotopic mass:124.906394(2) u (atomic weight of Xenon-125)Nuclide mass:124.8767726 u (calculated nuclear mass without electrons)Mass excess:-87.19343 MeVMass defect:1.131366764 u (per nucleus)Nuclear binding energy:1053.86135247 MeV (per nucleus)
8.43089082 MeV (average binding energy per nucleon)Separation energy:SN = 7.6033(4) MeV (first neutron)
SP = 7.1166(29) MeV (first proton)Half-life:16.9(2) hDecay constant λ:1.139295168573 × 10-5 s-1Specific activity α:5.533061279188 × 10+16 Bq g-1
1495421.9673481 Ci g-1Spin and parity:
(nuclear angular momentum)1/2(+)Magnetic dipole moment:μ(μN) = - 0.269(3)Nuclear g-factor:gl = -0.538Year of discovery:1950
Radioactive Decay
Half-life T½ = 16.9(2) h (hours) respectively 6.0840 × 104 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| EC/β+ | 125I | 100 % | 1.6438(24) MeV | |
Parent Nuclides
Direct parent isotope is: 125Cs.
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 |
|---|
| 125m1Xe | 252.61(14) keV | 57(1) s | 9/2(-) |
| 125m2Xe | 295.89(15) keV | 0.14(3) μs | 7/2(+) |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 71) and isobaric (same nucleon number A = 125) with Xenon-125. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 71 | Isobar A = 125 |
|---|
| 40 | 111Zr | |
| 41 | 112Nb | |
| 42 | 113Mo | |
| 43 | 114Tc | |
| 44 | 115Ru | |
| 45 | 116Rh | 125Rh |
| 46 | 117Pd | 125Pd |
| 47 | 118Ag | 125Ag |
| 48 | 119Cd | 125Cd |
| 49 | 120In | 125In |
| 50 | 121Sn | 125Sn |
| 51 | 122Sb | 125Sb |
| 52 | 123Te | 125Te |
| 53 | 124I | 125I |
| 54 | 125Xe | 125Xe |
| 55 | 126Cs | 125Cs |
| 56 | 127Ba | 125Ba |
| 57 | 128La | 125La |
| 58 | 129Ce | 125Ce |
| 59 | 130Pr | 125Pr |
| 60 | 131Nd | 125Nd |
| 61 | 132Pm | |
| 62 | 133Sm | |
| 63 | 134Eu | |
| 64 | 135Gd | |
| 65 | 136Tb | |
External data and identifiers
Last update: 2020-10-18
Perma link: https://www.chemlin.org/isotope/xenon-125
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