Lead-199
Properties and data of the isotope 199Pb.
See also: List of individual Lead isotopes (and general data sources).
General data
Name of the isotope:Lead-199; Pb-199Symbol:199Pb or 19982PbMass number A:199 (= number of nucleons)Atomic number Z:82 (= number of protons)Neutrons N:117Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.4268292682927 (= neutron-proton ratio)Neutron excess (N-Z):35Isotopic mass:198.972913(11) u (atomic weight of Lead-199)Nuclide mass:198.9279346 u (calculated nuclear mass without electrons)Mass excess:-25.23138 MeVMass defect:1.682534796 u (per nucleus)Nuclear binding energy:1567.27106727 MeV (per nucleus)
7.87573401 MeV (average binding energy per nucleon)Separation energy:SN = 7.236(13) MeV (first neutron)
SP = 4.992(13) MeV (first proton)Half-life:90(10) minDecay constant λ:0.00012836058899258 s-1Specific activity α:3.904068423120 × 10+17 Bq g-1
10551536.278703 Ci g-1Spin and parity:
(nuclear angular momentum)3/2-Magnetic dipole moment:μ(μN) = - 1.0742(12)Quadrupole moment Q:+ 0.08 barn (100 fm2)Nuclear g-factor:gl = -0.71613333333333Charge radius:5..4529(22) femtometer fmYear of discovery:1950
Radioactive Decay
Half-life T½ = 90(10) min (minutes) respectively 5.400 × 103 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| β+ | 199Tl | 100 % | 2.83(3) MeV | |
Parent Nuclides
Direct parent isotopes are: 199Bi, 203Po.
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 |
|---|
| 199m1Pb | 424.8(2)+x keV | 12.2(3) min | (13/2+) |
| 199m2Pb | 2559.7(4)+x keV | 10.1(2) μs | (29/2-) |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 117) and isobaric (same nucleon number A = 199) with Lead-199. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 117 | Isobar A = 199 |
|---|
| 71 | 188Lu | |
| 72 | 189Hf | |
| 73 | 190Ta | |
| 74 | 191W | |
| 75 | 192Re | 199Re |
| 76 | 193Os | 199Os |
| 77 | 194Ir | 199Ir |
| 78 | 195Pt | 199Pt |
| 79 | 196Au | 199Au |
| 80 | 197Hg | 199Hg |
| 81 | 198Tl | 199Tl |
| 82 | 199Pb | 199Pb |
| 83 | 200Bi | 199Bi |
| 84 | 201Po | 199Po |
| 85 | 202At | 199At |
| 86 | 203Rn | 199Rn |
| 87 | 204Fr | 199Fr |
| 88 | 205Ra | |
| 89 | 206Ac | |
| 90 | 207Th | |
External data and identifiers
Last update: 2020-10-22
Perma link: https://www.chemlin.org/isotope/lead-199
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