Het chemisch element uranium (U), met een atoommassa van 238,02891(3) u, bezit geen stabiele isotopen en wordt dus geclassificeerd als radioactief element.
In de natuur komen sporen van de radio-isotopen 234U en 235U voor. De isotoop 238U, met een halfwaardetijd van ongeveer 4,6 miljard jaar, komt echter het meest voor: de natuurlijke abundantie bedraagt 99,27%.
De kortstlevende isotoop van uranium is 220U, met een halfwaardetijd van ongeveer 60 nanoseconden. De langstlevende is 238U, met een halfwaardetijd van 4,468 miljard jaar.
Overzicht
| Nuclide | Z (p) | N (n) | Isotopische massa (u) | Halveringstijd | Radioactief verval | VP | Kernspin | Isotopische verhouding (molfractie) |
Natuurlijk voorkomen (molfractie) |
|---|---|---|---|---|---|---|---|---|---|
| Excitatie-energie | |||||||||
| 217U | 92 | 125 | 217,02437(9) | 26(14) ms | 1/2− | ||||
| 218U | 92 | 126 | 218,02354(3) | 6(5) ms | α | 214Th | 0+ | ||
| 219U | 92 | 127 | 219,02492(6) | 55(25) ms | α | 215Th | 9/2+ | ||
| 220U | 92 | 128 | 220,02472(22) | 60 ns | α | 216Th | 0+ | ||
| β+ (zelden) | 220Pa | ||||||||
| 221U | 92 | 129 | 221,02640(11) | 700 ns | α | 217Th | 9/2+ | ||
| β+ (zelden) | 221Pa | ||||||||
| 222U | 92 | 130 | 222,02609(11) | 1,4(7) ms | α | 218Th | 0+ | ||
| β+ (10−6%) | 222Pa | ||||||||
| 223U | 92 | 131 | 223,02774(8) | 21(8) ms | α | 219Th | 7/2+ | ||
| 224U | 92 | 132 | 224,027605(27) | 940(270) ms | α | 220Th | 0+ | ||
| 225U | 92 | 133 | 225,02939 | 61(4) ms | α | 221Th | (5/2+) | ||
| 226U | 92 | 134 | 226,029339(14) | 269(6) ms | α | 222Th | 0+ | ||
| 227U | 92 | 135 | 227,031156(18) | 1,1(1) min | α | 223Th | (3/2+) | ||
| β+ (0,001%) | 227Pa | ||||||||
| 228U | 92 | 136 | 228,031374(16) | 9,1(2) min | α (95%) | 224Th | 0+ | ||
| EV (5%) | 228Pa | ||||||||
| 229U | 92 | 137 | 229,033506(6) | 58(3) min | β+ (80%) | 229Pa | (3/2+) | ||
| α (20%) | 225Th | ||||||||
| 230U | 92 | 138 | 230,033940(5) | 20,8 dagen | α | 226Th | 0+ | ||
| SS (1,4 × 10−10%) | |||||||||
| β+β+ (zelden) | 230Th | ||||||||
| 231U | 92 | 139 | 231,036294(3) | 4,2(1) dagen | EV | 231Pa | (5/2+) | ||
| α (0,004%) | 227Th | ||||||||
| 232U | 92 | 140 | 232,0371562(24) | 68,9(4) jaar | α | 228Th | 0+ | ||
| CV (8,9 × 10−10%) | 208Pb, 24Ne | ||||||||
| CV (5 × 10−12%) | 204Hg, 28Mg | ||||||||
| SS (10−12%) | |||||||||
| 233U | 92 | 141 | 233,0396352(29) | 1,592(2) × 105 jaar | α | 229Th | 5/2+ | ||
| SS (6 × 10−9%) | |||||||||
| CV (7,2 × 10−11%) | 209Pb, 24Ne | ||||||||
| CV (1,3 × 10−13%) | 205Hg, 28Mg | ||||||||
| 234U | 92 | 142 | 234,0409521(20) | 2,455(6) × 105 jaar | α | 230Th | 0+ | 0,000054(5) | 0,000050 - 0,000059 |
| SS (1,73 × 10−9%) | |||||||||
| CV (1,4 × 10−11%) | 206Hg, 28Mg | ||||||||
| CV (9 × 10−12%) | 184Hf, 26Ne, 24Ne | ||||||||
| 234mU | 1421,32(10) keV | 33,5(20) ms | 6− | ||||||
| 235U | 92 | 143 | 235,0439299(20) | 7,04(1) × 108 jaar | α | 231Th | 7/2− | 0,007204(6) | 0,007198 - 0,007207 |
| SS (7 × 10−9%) | |||||||||
| CV (8 × 10−10%) | 186Hf, 25Ne, 24Ne | ||||||||
| 235mU | 0,0765(4) keV | ± 26 min | IT | 235U | 1/2+ | ||||
| 236U | 92 | 144 | 236,045568(2) | 2,342(3) × 107 jaar | α | 232Th | 0+ | ||
| SS (9,6 × 10−8%) | |||||||||
| 236m1U | 1052,89(19) keV | 100(4) ns | 4− | ||||||
| 236m2U | 2750(10) keV | 120(2) ns | (0+) | ||||||
| 237U | 92 | 145 | 237,0487302(20) | 6,75(1) dagen | β− | 237Np | 1/2+ | ||
| 238U | 92 | 146 | 238,0507882(20) | 4,468(3) × 109 jaar | α | 234Th | 0+ | 0,992742(10) | 0,992739 - 0,992752 |
| SS (5,45 × 10−5%) | |||||||||
| β−β− (2,19 × 10−10%) | 238Pu | ||||||||
| 238mU | 2557,9(5) keV | 280(6) ns | 0+ | ||||||
| 239U | 92 | 147 | 239,0542933(21) | 23,45(2) min | β− | 239Np | 5/2+ | ||
| 239m1 | 20(20) keV | > 250 ns | (5/2+) | ||||||
| 239m2U | 133,7990(10) keV | 780(40) ns | 1/2+ | ||||||
| 240U | 92 | 148 | 240,056592(6) | 14,1(1) uur | β− | 240Np | 0+ | ||
| α (10−10%) | 236Th | ||||||||
| 241U | 92 | 149 | 241,06033(32) | 5 min | β− | 241Np | 7/2+ | ||
| 242U | 92 | 150 | 242,06293(22) | 16,8(5) min | β− | 242Np | 0+ | ||
Overzicht van isotopen per element
| 1 | 18 | |||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | H | 2 | Periodiek systeem | 13 | 14 | 15 | 16 | 17 | He | |||||||||
| 2 | Li | Be | De links verwijzen naar isotopen per element | B | C | N | O | F | Ne | |||||||||
| 3 | Na | Mg | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | Al | Si | P | S | Cl | Ar |
| 4 | K | Ca | Sc | Ti | V | Cr | Mn | Fe | Co | Ni | Cu | Zn | Ga | Ge | As | Se | Br | Kr |
| 5 | Rb | Sr | Y | Zr | Nb | Mo | Tc | Ru | Rh | Pd | Ag | Cd | In | Sn | Sb | Te | I | Xe |
| 6 | Cs | Ba | ↓ | Hf | Ta | W | Re | Os | Ir | Pt | Au | Hg | Tl | Pb | Bi | Po | At | Rn |
| 7 | Fr | Ra | ↓↓ | Rf | Db | Sg | Bh | Hs | Mt | Ds | Rg | Cn | Nh | Fl | Mc | Lv | Ts | Og |
| Lanthaniden | La | Ce | Pr | Nd | Pm | Sm | Eu | Gd | Tb | Dy | Ho | Er | Tm | Yb | Lu | |||
| Actiniden | Ac | Th | Pa | U | Np | Pu | Am | Cm | Bk | Cf | Es | Fm | Md | No | Lr | |||
Bronnen, noten en/of referenties
- (en) R.B. Firestone, S.Y. Frank Chu & C.M. Baglin (1999) - Table of Isotopes (online versie van de cd-rom)
- (en) G. Audi, A.H. Wapstra, C. Thibault, J. Blachot & O. Bersillon (2003) - The NUBASE evaluation of nuclear and decay properties, Nuclear Physics A, 729, pp. 3-128
- (en) J.R. de Laeter, J.K. Böhlke, P. De Bièvre, H. Hidaka, H.S. Peiser, K.J.R. Rosman & P.D.P. Taylor (2003) - Atomic weights of the elements. Review 2000 (IUPAC Technical Report), Pure and Applied Chemistry, 75 (6), pp. 683–800
- (en) M.E. Wieser (2006) - Atomic weights of the elements 2005 (IUPAC Technical Report), Pure and Applied Chemistry, 78 (11), pp. 2051–2066
- (en) David R. Lide (2004) - CRC Handbook of Chemistry and Physics (85th ed.), hoofdstuk 11, CRC Press - ISBN 978-0849304859
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