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Naturally occurring zinc (30Zn) is composed of the 5 stable isotopes 64Zn, 66Zn, 67Zn, 68Zn, and 70Zn with 64Zn being the most abundant (48.6% natural abundance). Twenty-five radioisotopes have been characterised with the most abundant and stable being 65Zn with a half-life of 244.26 days, and 72Zn with a half-life of 46.5 hours. All of the remaining radioactive isotopes have half-lives that are less than 14 hours and the majority of these have half-lives that are less than 1 second. This element also has 10 meta states.

Main isotopes of zinc (30Zn)
Iso­tope Decay
abun­dance half-life (t1/2) mode pro­duct
64Zn 49.2% stable
65Zn syn 244 d ε 65Cu
γ
66Zn 27.7% stable
67Zn 4.0% stable
68Zn 18.5% stable
69Zn syn 56 min β 69Ga
69mZn syn 13.8 h β 69Ga
70Zn 0.6% stable
71Zn syn 2.4 min β 71Ga
71mZn syn 4 h β 71Ga
72Zn syn 46.5 h β 72Ga
Standard atomic weight Ar, standard(Zn)

Zinc has been proposed as a "salting" material for nuclear weapons. A jacket of isotopically enriched 64Zn, irradiated by the intense high-energy neutron flux from an exploding thermonuclear weapon, would transmute into the radioactive isotope 65Zn with a half-life of 244 days and produce approximately 1.115 MeV[2] of gamma radiation, significantly increasing the radioactivity of the weapon's fallout for several days. Such a weapon is not known to have ever been built, tested, or used.[3]

List of isotopesEdit

Nuclide
[n 1]
Z N Isotopic mass (u)
[n 2][n 3]
Half-life
[n 4]
Decay
mode

[n 5]
Daughter
isotope

[n 6]
Spin and
parity
[n 7][n 4]
Natural abundance (mole fraction)
Excitation energy Normal proportion Range of variation
54Zn 30 24 53.99295(43)# 2p 52Ni 0+
55Zn 30 25 54.98398(27)# 20# ms [>1.6 µs] 2p 53Ni 5/2−#
β+ 55Cu
56Zn 30 26 55.97238(28)# 36(10) ms β+ 56Cu 0+
57Zn 30 27 56.96479(11)# 38(4) ms β+, p (65%) 56Ni 7/2−#
β+ (35%) 57Cu
58Zn 30 28 57.95459(5) 84(9) ms β+, p (60%) 57Ni 0+
β+ (40%) 58Cu
59Zn 30 29 58.94926(4) 182.0(18) ms β+ (99%) 59Cu 3/2−
β+, p (1%) 58Ni
60Zn[n 8] 30 30 59.941827(11) 2.38(5) min β+ 60Cu 0+
61Zn 30 31 60.939511(17) 89.1(2) s β+ 61Cu 3/2−
61m1Zn 88.4(1) keV <430 ms 1/2−
61m2Zn 418.10(15) keV 140(70) ms 3/2−
61m3Zn 756.02(18) keV <130 ms 5/2−
62Zn 30 32 61.934330(11) 9.186(13) h β+ 62Cu 0+
63Zn 30 33 62.9332116(17) 38.47(5) min β+ 63Cu 3/2−
64Zn 30 34 63.9291422(7) Observationally Stable[n 9] 0+ 0.4917(75)
65Zn 30 35 64.9292410(7) 243.66(9) d β+ 65Cu 5/2−
65mZn 53.928(10) keV 1.6(6) µs (1/2)−
66Zn 30 36 65.9260334(10) Stable 0+ 0.2773(98)
67Zn 30 37 66.9271273(10) Stable 5/2− 0.0404(16)
68Zn 30 38 67.9248442(10) Stable 0+ 0.1845(63)
69Zn 30 39 68.9265503(10) 56.4(9) min β 69Ga 1/2−
69mZn 438.636(18) keV 13.76(2) h IT (96.7%) 69Zn 9/2+
β (3.3%) 69Ga
70Zn 30 40 69.9253193(21) Observationally Stable[n 10] 0+ 0.0061(10)
71Zn 30 41 70.927722(11) 2.45(10) min β 71Ga 1/2−
71mZn 157.7(13) keV 3.96(5) h β (99.95%) 71Ga 9/2+
IT (.05%) 71Zn
72Zn 30 42 71.926858(7) 46.5(1) h β 72Ga 0+
73Zn 30 43 72.92978(4) 23.5(10) s β 73Ga (1/2)−
73m1Zn 195.5(2) keV 13.0(2) ms (5/2+)
73m2Zn 237.6(20) keV 5.8(8) s β 73Ga (7/2+)
IT 73Zn
74Zn 30 44 73.92946(5) 95.6(12) s β 74Ga 0+
75Zn 30 45 74.93294(8) 10.2(2) s β 75Ga (7/2+)#
76Zn 30 46 75.93329(9) 5.7(3) s β 76Ga 0+
77Zn 30 47 76.93696(13) 2.08(5) s β 77Ga (7/2+)#
77mZn 772.39(12) keV 1.05(10) s IT (50%) 77Zn 1/2−#
β (50%) 77Ga
78Zn 30 48 77.93844(10) 1.47(15) s β 78Ga 0+
78mZn 2673(1) keV 319(9) ns (8+)
79Zn 30 49 78.94265(28)# 0.995(19) s β (98.7%) 79Ga (9/2+)
β, n (1.3%) 78Ga
80Zn 30 50 79.94434(18) 545(16) ms β (99%) 80Ga 0+
β, n (1%) 79Ga
81Zn 30 51 80.95048(32)# 290(50) ms β (92.5%) 81Ga 5/2+#
β, n (7.5%) 80Ga
82Zn 30 52 81.95442(54)# 100# ms [>300 ns] β 82Ga 0+
83Zn 30 53 82.96103(54)# 80# ms [>300 ns] 5/2+#
  1. ^ mZn – Excited nuclear isomer.
  2. ^ ( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.
  3. ^ # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
  4. ^ a b # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
  5. ^ Modes of decay:
    IT: Isomeric transition
    n: Neutron emission
    p: Proton emission
  6. ^ Bold symbol as daughter – Daughter product is stable.
  7. ^ ( ) spin value – Indicates spin with weak assignment arguments.
  8. ^ Final product of the silicon-burning process; its production is endothermic and accelerates the star's collapse
  9. ^ Believed to undergo β+β+ decay to 64Ni with a half-life over 2.3×1018 a
  10. ^ Believed to undergo ββ decay to 70Ge with a half-life over 1.3×1016 a

ReferencesEdit

  1. ^ Meija, Juris; et al. (2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)". Pure and Applied Chemistry. 88 (3): 265–91. doi:10.1515/pac-2015-0305.
  2. ^ Roost, E.; Funck, E.; Spernol, A.; Vaninbroukx, R. (1972). "The decay of 65Zn". Zeitschrift für Physik. 250 (5): 395–412. Bibcode:1972ZPhy..250..395D. doi:10.1007/BF01379752.
  3. ^ D. T. Win, M. Al Masum (2003). "Weapons of Mass Destruction" (PDF). Assumption University Journal of Technology. 6 (4): 199–219.

External linksEdit