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Although phosphorus (15P) has 23 isotopes from 25P to 47P, only 31P is stable; as such, phosphorus is considered a monoisotopic element. The longest-lived radioactive isotopes are 33P with a half-life of 25.34 days and 32P with a half-life of 14.263 days. All others have half-lives of under 2.5 minutes, most under a second. The least stable is 25P with a half-life shorter than 30 nanoseconds.

Main isotopes of phosphorus (15P)
Iso­tope Decay
abun­dance half-life (t1/2) mode pro­duct
31P 100% stable
32P trace 14.28 d β 32S
33P trace 25.3 d β 33S
Standard atomic weight Ar, standard(P)
  • 30.973761998(5)[1]

Contents

List of isotopesEdit

Nuclide[2]
[n 1]
Z N Isotopic mass (u)[3]
[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
25P 15 10 25.02119(43)# <30 ns p 24Si (1/2+)#
26P[n 8] 15 11 26.01178(21)# 43.7(6) ms β+ (63.2%) 26Si (3+)
β+, p (36.8%) 25Al
26mP 164.4(1) keV 120(9) ns IT 26P
27P 15 12 26.999224(28) 260(80) ms β+ (99.93%) 27Si 1/2+
β+, p (.07%) 26Al
28P 15 13 27.9923266(12) 270.3(5) ms β+ (99.99%) 28Si 3+
β+, p (.0013%) 27Al
β+, α (8.6×10−4%) 24Mg
29P 15 14 28.9818004(4) 4.142(15) s β+ 29Si 1/2+
30P 15 15 29.97831349(7) 2.498(4) min β+ 30Si 1+
31P 15 16 30.9737619986(7) Stable 1/2+ 1.0000
32P 15 17 31.97390764(4) 14.268(5) d β 32S 1+ Trace
33P 15 18 32.9717257(12) 25.35(11) d β 33S 1/2+
34P 15 19 33.9736459(9) 12.43(10) s β 34S 1+
35P 15 20 34.9733141(20) 47.3(8) s β 35S 1/2+
36P 15 21 35.978260(14) 5.6(3) s β 36S 4−
37P 15 22 36.97961(4) 2.31(13) s β 37S (1/2+)
38P 15 23 37.98430(8) 0.64(14) s β (87.5%) 38S
β, n (12.5%) 37S
39P 15 24 38.98629(12) 282(24) ms β (73.2%) 39S 1/2+#
β, n (26.8%) 38S
40P 15 25 39.99129(16) 150(8) ms β (84.2%) 40S (2−,3−)
β, n (15.8%) 39S
41P 15 26 40.99465(13) 101(5) ms β (70%) 41S 1/2+#
β, n (30%) 40S
42P 15 27 42.00108(34) 48.5(15) ms β (50%) 42S
β, n (50%) 41S
43P 15 28 43.00502(60) 35.8(13) ms β, n 42S 1/2+#
β 43S
44P 15 29 44.01122(54)# 18.5(25) ms β 44S
45P 15 30 45.01675(54)# 8# ms [>200 ns] β 45S 1/2+#
46P 15 31 46.02466(75)# 4# ms [>200 ns] β 46S
47P[4] 15 32 47.03190(86)# 2# ms β 47S
  1. ^ mP – 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. ^ Has 1 halo proton

Radioactive isotopesEdit

Phosphorus-32Edit

32P, a beta-emitter (1.71 MeV) with a half-life of 14.3 days, is used routinely in life-science laboratories, primarily to produce radiolabeled DNA and RNA probes, e.g. for use in Northern blots or Southern blots. Because the high-energy beta particles produced penetrate skin and corneas, and because any 32P ingested, inhaled, or absorbed is readily incorporated into bone and nucleic acids, OSHA requires that a lab coat, disposable gloves, and safety glasses or goggles be worn when working with 32P, and that working directly over an open container be avoided in order to protect the eyes.[citation needed] Monitoring personal, clothing, and surface contamination is also required. In addition, due to the high energy of the beta particles, shielding this radiation with the normally used dense materials (e.g. lead), gives rise to secondary emission of X-rays via a process known as bremsstrahlung, meaning braking radiation. Therefore, shielding must be accomplished with low-density materials, e.g. Plexiglas, Lucite, plastic, wood, or water.

Phosphorus-33Edit

33P, a beta-emitter (0.25 MeV) with a half-life of 25.4 days. It is used in life-science laboratories in applications in which lower energy beta emissions are advantageous such as DNA sequencing. 33P can be used to label nucleotides. It is less energetic than 32P, giving a better resolution. A disadvantage is its higher cost compared to 32P, as most of the bombarded 31P will have acquired only one neutron, while only some will have acquired two or more. Its maximum specific activity is 5118 Ci/mol.

ReferencesEdit

  • Isotope masses from:
    • Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties", Nuclear Physics A, 729: 3–128, Bibcode:2003NuPhA.729....3A, doi:10.1016/j.nuclphysa.2003.11.001
  • Isotopic compositions and standard atomic masses from:
  • Half-life, spin, and isomer data selected from the following sources.

External linksEdit

  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. ^ Half-life, decay mode, nuclear spin, and isotopic composition is sourced in:
    Audi, G.; Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S. (2017), "The NUBASE2016 evaluation of nuclear properties" (PDF), Chinese Physics C, 41 (3): 030001–1—030001–138, Bibcode:2017ChPhC..41c0001A, doi:10.1088/1674-1137/41/3/030001
  3. ^ Wang, Meng; Audi, Georges; Kondev, Filip G.; Huang, Wen Jian; Naimi, Sarah; Xu, Xing (2017), "The AME2016 atomic mass evaluation (II). Tables, graphs, and references" (PDF), Chinese Physics C, 41 (3): 030003–1—030003–442, doi:10.1088/1674-1137/41/3/030003
  4. ^ Neufcourt, L.; Cao, Y.; Nazarewicz, W.; Olsen, E.; Viens, F. (2019). "Neutron drip line in the Ca region from Bayesian model averaging". Physical Review Letters. 122: 062502–1—062502–6. arXiv:1901.07632. doi:10.1103/PhysRevLett.122.062502.