See also: List of individual Zinc isotopes (and general data sources).
General data
Name of the isotope:Zinc-70; Zn-70Symbol:70Zn or 7030ZnMass number A:70 (= number of nucleons)Atomic number Z:30 (= number of protons)Neutrons N:40Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.3333333333333 (= neutron-proton ratio)Neutron excess (N-Z):10Isotopic mass:69.92532(2) u (atomic weight of Zinc-70)Nuclide mass:69.9088631 u (calculated nuclear mass without electrons)Mass excess:-69.56397 MeVMass defect:0.6560276 u (per nucleus)Nuclear binding energy:611.08577323 MeV (per nucleus) 8.72979676 MeV (average binding energy per nucleon)Separation energy:SN = 9.2182(20) MeV (first neutron) SP = 11.1175(24) MeV (first proton)Half-life:3.8 × 1018 yearsDecay constant λ:5.784092870970 × 10-27 s-1Specific activity α:4.981403222451 × 10-5 Bq g-1 1.346325195257 × 10-15 Ci g-1Spin and parity: (nuclear angular momentum)0+Charge radius:3.9845(19) femtometer fmYear of discovery:1922
Radioactive Decay
Half-life T½ = 3.8 × 1018 years respectively 1.198368 × 1026 seconds s.
Comparison of the natural Zinc isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):
Atomic Mass ma
Quantity
Half-life
Spin
Zinc Isotopic mixture
65.38 u
100 %
Isotope 64Zn
63.929142(5) u
49.17(75) %
stable
0+
Isotope 66Zn
65.926034(6) u
27.73(98) %
stable
0+
Isotope 67Zn
66.9271274(8) u
4.04(16) %
stable
5/2-
Isotope 68Zn
67.924845(6) u
18.45(63) %
stable
0+
Isotope 70Zn
69.92532(2) u
0.61(10) %
3.8 × 1018 years
0+
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 40) and isobaric (same nucleon number A = 70) with Zinc-70. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
