Lead-194

Properties and data of the isotope ¹⁹⁴Pb.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

See also: List of individual Lead isotopes (and general data sources).

General data

Name of the isotope:Lead-194; Pb-194Symbol:¹⁹⁴Pb or 19482PbMass number A:194 (= number of nucleons)Atomic number Z:82 (= number of protons)Neutrons N:112Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.3658536585366 (= neutron-proton ratio)Neutron excess (N-Z):30Isotopic mass:193.974012(19) u (atomic weight of Lead-194)Nuclide mass:193.9290336 u (calculated nuclear mass without electrons)Mass excess:-24.20767 MeVMass defect:1.638111216 u (per nucleus)Nuclear binding energy:1525.89076904 MeV (per nucleus)
7.86541634 MeV (average binding energy per nucleon)Separation energy:S_N = 10.08(5) MeV (first neutron)
S_P = 4.020(19) MeV (first proton)Half-life:10.7(6) minDecay constant λ:0.0010796685055451 s^-1Specific activity α:3.368868301777 × 10⁺¹⁸ Bq g^-1
91050494.642627 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Charge radius:5.4372(23) femtometer fmYear of discovery:1960

Radioactive Decay

Half-life T_½ = 10.7(6) min (minutes) respectively 6.42 × 10² seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β⁺	¹⁹⁴Tl	> 99.9 %	2.73(22) MeV
α	¹⁹⁰Hg	trace	4.738(17) MeV

Parent Nuclides

Direct parent isotopes are: ¹⁹⁴Bi, ¹⁹⁸Po.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 112) and isobaric (same nucleon number A = 194) with Lead-194. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 112	Isobar A = 194
70	¹⁸²Yb
71	¹⁸³Lu
72	¹⁸⁴Hf
73	¹⁸⁵Ta	¹⁹⁴Ta
74	¹⁸⁶W	¹⁹⁴W
75	¹⁸⁷Re	¹⁹⁴Re
76	¹⁸⁸Os	¹⁹⁴Os
77	¹⁸⁹Ir	¹⁹⁴Ir
78	¹⁹⁰Pt	¹⁹⁴Pt
79	¹⁹¹Au	¹⁹⁴Au
80	¹⁹²Hg	¹⁹⁴Hg
81	¹⁹³Tl	¹⁹⁴Tl
82	¹⁹⁴Pb	¹⁹⁴Pb
83	¹⁹⁵Bi	¹⁹⁴Bi
84	¹⁹⁶Po	¹⁹⁴Po
85	¹⁹⁷At	¹⁹⁴At
86	¹⁹⁸Rn	¹⁹⁴Rn
87	¹⁹⁹Fr