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Isotopes of sodium



There are thirteen recognized isotopes of sodium. 23Na is the only stable isotope. As such, it is considered a monoisotopic element and it has a standard atomic mass: 22.98976928(2) u. Sodium has two radioactive cosmogenic isotopes (22Na, half-life = 2.605 years; and 24Na, half-life ≈ 15 hours).

Additional recommended knowledge

Acute neutron radiation exposure (e.g., from a nuclear criticality accident) converts some of the stable 23Na in human blood plasma to 24Na. By measuring the concentration of this isotope, the neutron radiation dosage to the victim can be computed.

Table

nuclide
symbol
Z(p) N(n)  
isotopic mass (u)
 
half-life nuclear
spin
representative
isotopic
composition
(mole fraction)
range of natural
variation
(mole fraction)
excitation energy
18Na 11 7 18.02597(5) 1.3(4)E-21 s (1-)#
19Na 11 8 19.013877(13) <40 ns (5/2+)#
20Na 11 9 20.007351(7) 447.9(23) ms 2+
21Na 11 10 20.9976552(8) 22.49(4) s 3/2+
22Na 11 11 21.9944364(4) 2.6027(10) yr 3+
22mNa 583.03(9) keV 244(6) ns 1+
23Na 11 12 22.9897692809(29) STABLE 3/2+ 1.0000
24Na 11 13 23.99096278(8) 14.9590(12) h 4+
24mNa 472.207(9) keV 20.20(7) ms 1+
25Na 11 14 24.9899540(13) 59.1(6) s 5/2+
26Na 11 15 25.992633(6) 1.077(5) s 3+
27Na 11 16 26.994077(4) 301(6) ms 5/2+
28Na 11 17 27.998938(14) 30.5(4) ms 1+
29Na 11 18 29.002861(14) 44.9(12) ms 3/2(+#)
30Na 11 19 30.008976(27) 48.4(17) ms 2+
31Na 11 20 31.01359(23) 17.0(4) ms (3/2+)
32Na 11 21 32.02047(38) 12.9(7) ms (3-,4-)
33Na 11 22 33.02672(94) 8.2(2) ms 3/2+#
34Na 11 23 34.03517(96)# 5.5(10) ms 1+
35Na 11 24 35.04249(102)# 1.5(5) ms 3/2+#
36Na 11 25 36.05148(102)# <260 ns
37Na 11 26 37.05934(103)# 1# ms [>1.5 µs] 3/2+#

Notes

  • Values marked # are not purely derived from experimental data, but at least partly from systematic trends. Spins with weak assignment arguments are enclosed in parentheses.
  • Uncertainties are given in concise form in parentheses after the corresponding last digits. Uncertainty values denote one standard deviation, except isotopic composition and standard atomic mass from IUPAC which use expanded uncertainties.

References

  • Isotope masses from Ame2003 Atomic Mass Evaluation by G. Audi, A.H. Wapstra, C. Thibault, J. Blachot and O. Bersillon in Nuclear Physics A729 (2003).
  • Isotopic compositions and standard atomic masses from Atomic weights of the elements. Review 2000 (IUPAC Technical Report). Pure Appl. Chem. Vol. 75, No. 6, pp. 683-800, (2003) and Atomic Weights Revised (2005).
  • Half-life, spin, and isomer data selected from these sources. Editing notes on this article's talk page.
    • Audi, Bersillon, Blachot, Wapstra. The Nubase2003 evaluation of nuclear and decay properties, Nuc. Phys. A 729, pp. 3-128 (2003).
    • National Nuclear Data Center, Brookhaven National Laboratory. Information extracted from the NuDat 2.1 database (retrieved Sept. 2005).
    • David R. Lide (ed.), Norman E. Holden in CRC Handbook of Chemistry and Physics, 85th Edition, online version. CRC Press. Boca Raton, Florida (2005). Section 11, Table of the Isotopes.


Isotopes of neon Isotopes of sodium Isotopes of magnesium
Index to isotope pages
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Isotopes_of_sodium". A list of authors is available in Wikipedia.
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