See also: List of individual Germanium isotopes (and general data sources).
General data
Name of the isotope:Germanium-70; Ge-70Symbol:70Ge or 7032GeMass number A:70 (= number of nucleons)Atomic number Z:32 (= number of protons)Neutrons N:38Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.1875 (= neutron-proton ratio)Neutron excess (N-Z):6Isotopic mass:69.924249(6) u (atomic weight of Germanium-70)Nuclide mass:69.906695 u (calculated nuclear mass without electrons)Mass excess:-70.5616 MeVMass defect:0.655418832 u (per nucleus)Nuclear binding energy:610.5187095 MeV (per nucleus) 8.72169585 MeV (average binding energy per nucleon)Separation energy:SN = 11.5325(16) MeV (first neutron) SP = 8.5230(15) MeV (first proton)Half-life:stableSpin and parity: (nuclear angular momentum)0+Charge radius:4.0414(11) femtometer fmYear of discovery:1923
Comparison of the natural Germanium isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):
Atomic Mass ma
Quantity
Half-life
Spin
Germanium Isotopic mixture
72.630 u
100 %
Isotope 70Ge
69.924249(6) u
20.52(19) %
stable
0+
Isotope 72Ge
71.9220758(5) u
27.45(15) %
stable
0+
Isotope 74Ge
73.92117776(9) u
36.52(12) %
stable
0+
Isotope 76Ge
75.9214027(2) u
7.75(12) %
1.926(94) × 1021 years
0+
Isotope 73Ge
72.92345895(6) u
7.76(8) %
stable
9/2+
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 38) and isobaric (same nucleon number A = 70) with Germanium-70. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
