See also: List of individual Mercury isotopes (and general data sources).
General data
Name of the isotope:Mercury-178; Hg-178Symbol:178Hg or 17880HgMass number A:178 (= number of nucleons)Atomic number Z:80 (= number of protons)Neutrons N:98Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.225 (= neutron-proton ratio)Neutron excess (N-Z):18Isotopic mass:177.982484(12) u (atomic weight of Mercury-178)Nuclide mass:177.9386024 u (calculated nuclear mass without electrons)Mass excess:-16.31605 MeVMass defect:1.492680328 u (per nucleus)Nuclear binding energy:1390.42276945 MeV (per nucleus) 7.81136387 MeV (average binding energy per nucleon)Separation energy:SN = 11.60(8) MeV (first neutron) SP = 20.60(15) MeV (first proton)Half-life:266.5(24) msDecay constant λ:2.6009275067915 s-1Specific activity α:8.800389341939 × 10+21 Bq g-1 237848360592.95 Ci g-1Spin and parity: (nuclear angular momentum)0+Year of discovery:1971
Radioactive Decay
Half-life T½ = 266.5(24) ms respectively 2.665 × 10-1 seconds s.
The following table shows the atomic nuclei that are isotonic (same neutron number N = 98) and isobaric (same nucleon number A = 178) with Mercury-178. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
