Mercury-208

Properties and data of the isotope ²⁰⁸Hg.

Contents

General Data

Radioactive Decay

Isotones und Isobares

Literature

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

General data

Name of the isotope:Mercury-208; Hg-208Symbol:²⁰⁸Hg or 20880HgMass number A:208 (= number of nucleons)Atomic number Z:80 (= number of protons)Neutrons N:128Isotopic mass:207.98576(3) u (atomic weight of Mercury-208)Nuclide mass:207.9418784 u (calculated nuclear mass without electrons)Mass excess:-13.26447 MeVMass defect:1.749351808 u (per nucleus)Nuclear binding energy:1629.51071304 MeV (per nucleus)
7.83418612 MeV (average binding energy per nucleon)Separation energy:S_N = 4.85(4) MeV (first neutron)
S_P = 9.74(39) MeV (first proton)Half-life:41(5) minDecay constant λ:0.00028176714656908 s^-1Specific activity α:8.197301673147 × 10⁺¹⁷ Bq g^-1
22154869.386884 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Year of discovery:1994

Radioactive Decay

Half-life T_½ = 41(5) min (minutes) respectively 2.460 × 10³ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	²⁰⁸Tl	100 %	3.48(3) MeV

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 128) and isobaric (same nucleon number A = 208) with Mercury-208. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 128	Isobar A = 208
77	²⁰⁵Ir
78	²⁰⁶Pt	²⁰⁸Pt
79	²⁰⁷Au	²⁰⁸Au
80	²⁰⁸Hg	²⁰⁸Hg
81	²⁰⁹Tl	²⁰⁸Tl
82	²¹⁰Pb	²⁰⁸Pb
83	²¹¹Bi	²⁰⁸Bi
84	²¹²Po	²⁰⁸Po
85	²¹³At	²⁰⁸At
86	²¹⁴Rn	²⁰⁸Rn
87	²¹⁵Fr	²⁰⁸Fr
88	²¹⁶Ra	²⁰⁸Ra
89	²¹⁷Ac	²⁰⁸Ac
90	²¹⁸Th	²⁰⁸Th
91	²¹⁹Pa
92	²²⁰U
95	²²³Am