Xenon-120
Properties and data of the isotope 120Xe.
See also: List of individual Xenon isotopes (and general data sources).
General data
Name of the isotope:Xenon-120; Xe-120Symbol:120Xe or 12054XeMass number A:120 (= number of nucleons)Atomic number Z:54 (= number of protons)Neutrons N:66Isotopic mass:119.911784(13) u (atomic weight of Xenon-120)Nuclide mass:119.8821626 u (calculated nuclear mass without electrons)Mass excess:-82.17267 MeVMass defect:1.082652184 u (per nucleus)Nuclear binding energy:1008.48401348 MeV (per nucleus)
8.40403345 MeV (average binding energy per nucleon)Separation energy:SN = 11.449(16) MeV (first neutron)
SP = 5.70(3) MeV (first proton)Half-life:40(1) minDecay constant λ:0.00028881132523331 s-1Specific activity α:1.461565111344 × 10+18 Bq g-1
39501759.766068 Ci g-1Spin and parity:
(nuclear angular momentum)0+Charge radius:4.7509(63) femtometer fmYear of discovery:1965
Radioactive Decay
Half-life T½ = 40(1) min (minutes) respectively 2.400 × 103 seconds s.
Decay mode | Daughter | Probability | Decay energy | γ energy (intensity) |
|---|
| EC/β+ | 120I | 100 % | 1.581(19) MeV | |
Parent Nuclides
Direct parent isotope is: 120Cs.
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 66) and isobaric (same nucleon number A = 120) with Xenon-120. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 66 | Isobar A = 120 |
| 37 | 103Rb | |
| 38 | 104Sr | |
| 39 | 105Y | |
| 40 | 106Zr | |
| 41 | 107Nb | |
| 42 | 108Mo | |
| 43 | 109Tc | 120Tc |
| 44 | 110Ru | 120Ru |
| 45 | 111Rh | 120Rh |
| 46 | 112Pd | 120Pd |
| 47 | 113Ag | 120Ag |
| 48 | 114Cd | 120Cd |
| 49 | 115In | 120In |
| 50 | 116Sn | 120Sn |
| 51 | 117Sb | 120Sb |
| 52 | 118Te | 120Te |
| 53 | 119I | 120I |
| 54 | 120Xe | 120Xe |
| 55 | 121Cs | 120Cs |
| 56 | 122Ba | 120Ba |
| 57 | 123La | 120La |
| 58 | 124Ce | 120Ce |
| 59 | 125Pr | |
| 60 | 126Nd | |
| 61 | 127Pm | |
| 62 | 128Sm | |
External data and identifiers
Last update: 2020-10-18
Perma link: https://www.chemlin.org/isotope/xenon-120
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