Lead-218

Properties and data of the isotope ²¹⁸Pb.

Contents

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

General data

Name of the isotope:Lead-218; Pb-218Symbol:²¹⁸Pb or 21882PbMass number A:218 (= number of nucleons)Atomic number Z:82 (= number of protons)Neutrons N:136Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.6585365853659 (= neutron-proton ratio)Neutron excess (N-Z):54Isotopic mass:218.01659(32) u (atomic weight of Lead-218)Nuclide mass:217.9716116 u (calculated nuclear mass without electrons)Mass excess:15.45349 MeVMass defect:1.8034912 u (per nucleus)Nuclear binding energy:1679.94123185 MeV (per nucleus)
7.70615244 MeV (average binding energy per nucleon)Separation energy:S_N = 4.86(42) MeV (first neutron)
S_P = 10.15(50) MeV (first proton)Half-life:> 300 nsDecay constant λ:2310490.6018665 s^-1Specific activity α:6.382614614678 × 10⁺²⁷ Bq g^-1
1.725030976940 × 10⁺¹⁷ Ci g^-1Spin and parity:
(nuclear angular momentum)0+Year of discovery:2009

Radioactive Decay

Half-life T_½ = > 300 ns respectively 3.0 × 10^-7 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	²¹⁸Pb	?	2.24(30) MeV

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 136) and isobaric (same nucleon number A = 218) with Lead-218. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 136	Isobar A = 218
80	²¹⁶Hg
81	²¹⁷Tl
82	²¹⁸Pb	²¹⁸Pb
83	²¹⁹Bi	²¹⁸Bi
84	²²⁰Po	²¹⁸Po
85	²²¹At	²¹⁸At
86	²²²Rn	²¹⁸Rn
87	²²³Fr	²¹⁸Fr
88	²²⁴Ra	²¹⁸Ra
89	²²⁵Ac	²¹⁸Ac
90	²²⁶Th	²¹⁸Th
91	²²⁷Pa	²¹⁸Pa
92	²²⁸U	²¹⁸U
93	²²⁹Np
94	²³⁰Pu
95	²³¹Am
96	²³²Cm
97	²³³Bk