Isotopen van cerium
Het chemisch element cerium (Ce), met een atoommassa van 140,116(1) u, bezit 4 stabiele isotopen: 136Ce, 138Ce, 140Ce en 142Ce, waarvan de voorlaatst het meest abundant is (ongeveer 88,5%). De 35 radio-isotopen zijn onstabiel en hebben een relatief korte halveringstijd (de meeste minder dan een seconde).
De kortstlevende isotoop van cerium is 157Ce, met een halfwaardetijd van ongeveer 50 milliseconden. De langstlevende is 144Ce, met een halfwaardetijd van 284,893 dagen.
Stabiliteit
[bewerken | brontekst bewerken]De isotopen 136Ce, 138Ce en 142Ce worden ervan verdacht om via dubbel bètaverval te vervallen tot nog stabielere isotopen, maar dit is nooit waargenomen. Bovendien is de halfwaardetijd zodanig lang (bijvoorbeeld voor 136Ce is dat 38 biljard jaar), dat de isotopen als stabiel kunnen beschouwd worden. 140Ce is theoretisch gezien in staat om spontane splijting te ondergaan.
Overzicht
[bewerken | brontekst bewerken]| Nuclide | Z (p) | N (n) | Isotopische massa (u) | Halveringstijd | Radioactief verval | VP | Kernspin | Isotopische verhouding (molfractie) |
Natuurlijk voorkomen (molfractie) |
|---|---|---|---|---|---|---|---|---|---|
| Excitatie-energie | |||||||||
| 119Ce | 58 | 61 | 118,95276(64) | 200 ms | β+ | 119La | 5/2+ | ||
| 120Ce | 58 | 62 | 119,94664(75) | 250 ms | β+ | 120La | 0+ | ||
| 121Ce | 58 | 63 | 120,94342(54) | 1,1(1) s | β+ | 121La | (5/2+) | ||
| 122Ce | 58 | 64 | 121,93791(43) | 2 s | β+ | 122La | 0+ | ||
| β+, p | 121Ba | ||||||||
| 123Ce | 58 | 65 | 122,93540(32) | 3,8(2) s | β+ | 123La | (5/2+) | ||
| β+, p | 122Ba | ||||||||
| 124Ce | 58 | 66 | 123,93041(32) | 9,1(12) s | β+ | 124La | 0+ | ||
| 125Ce | 58 | 67 | 124,92844(21) | 9,3(3) s | β+ | 125La | (7/2−) | ||
| β+, p | 124Ba | ||||||||
| 126Ce | 58 | 68 | 125,92397(3) | 51,0(3) s | β+ | 126La | 0+ | ||
| 127Ce | 58 | 69 | 126,92273(6) | 29(2) s | β+ | 127La | 5/2+ | ||
| 128Ce | 58 | 70 | 127,91891(3) | 3,93(2) min | β+ | 128La | 0+ | ||
| 129Ce | 58 | 71 | 128,91810(3) | 3,5(3) min | β+ | 129La | (5/2+) | ||
| 130Ce | 58 | 72 | 129,91474(3) | 22,9(5) min | β+ | 130La | 0+ | ||
| 130mCe | 2453,6(3) keV | 100(8) ns | (7−) | ||||||
| 131Ce | 58 | 73 | 130,91442(4) | 10,2(3) min | β+ | 131La | (7/2+) | ||
| 131mCe | 61,8(1) keV | 5,0(10) min | β+ | 131La | (1/2+) | ||||
| 132Ce | 58 | 74 | 131,911460(22) | 3,51(11) uur | β+ | 132La | 0+ | ||
| 132mCe | 2340,8(5) keV | 9,4(3) ms | IT | 132Ce | (8−) | ||||
| 133Ce | 58 | 75 | 132,911515(18) | 97(4) min | β+ | 133La | 1/2+ | ||
| 133mCe | 37,1(8) keV | 4,9(4) uur | β+ | 133La | 9/2− | ||||
| 134Ce | 58 | 76 | 133,908925(22) | 3,16(4) dagen | EV | 134La | 0+ | ||
| 135Ce | 58 | 77 | 134,909151(12) | 17,7(3) uur | β+ | 135La | 1/2+ | ||
| 135mCe | 445,8(2) keV | 20(1) s | IT | 135Ce | (11/2−) | ||||
| 136Ce | 58 | 78 | 135,907172(14) | stabiel | 0+ | 0,00185(2) | 0,00185 - 0,00186 | ||
| 136mCe | 3095,5(4) keV | 2,2(2) µs | 10+ | ||||||
| 137Ce | 58 | 79 | 136,907806(14) | 9,0(3) uur | β+ | 137La | 3/2+ | ||
| 137mCe | 254,29(5) keV | 34,4(3) uur | IT (99,22%) | 137Ce | 11/2− | ||||
| β+ (0,779%) | 137La | ||||||||
| 138Ce | 58 | 80 | 137,905991(11) | stabiel | 0+ | 0,00251(2) | 0,00251 - 0,00254 | ||
| 138mCe | 2129,17(12) keV | 8,65(20) ms | IT | 138Ce | 7− | ||||
| 139Ce | 58 | 81 | 138,906653(8) | 137,641(20) dagen | EV | 139La | 3/2+ | ||
| 139mCe | 754,24(8) keV | 56,54(13) s | IT | 139Ce | 11/2− | ||||
| 140Ce | 58 | 82 | 139,9054387(26) | stabiel | 0+ | 0,88450(51) | 0,88446 - 0,88449 | ||
| 140mCe | 2107,85(3) keV | 7,3(15) µs | 6+ | ||||||
| 141Ce | 58 | 83 | 140,9082763(26) | 32,508(13) dagen | β− | 141Pr | 7/2− | ||
| 142Ce | 58 | 84 | 141,909244(3) | stabiel | 0+ | 0,11114(51) | 0,11114 - 0,11114 | ||
| 143Ce | 58 | 85 | 142,912386(3) | 33,039(6) uur | β− | 143Pr | 3/2− | ||
| 144Ce | 58 | 86 | 143,913647(4) | 284,91(5) dagen | β− | 144mPr | 0+ | ||
| 145Ce | 58 | 87 | 144,91723(4) | 3,01(6) min | β− | 145Pr | (3/2−) | ||
| 146Ce | 58 | 88 | 145,91876(7) | 13,52(13) min | β− | 146Pr | 0+ | ||
| 147Ce | 58 | 89 | 146,92267(3) | 56,4(10) s | β− | 147Pr | (5/2−) | ||
| 148Ce | 58 | 90 | 147,92443(3) | 56(1) s | β− | 148Pr | 0+ | ||
| 149Ce | 58 | 91 | 148,9284(1) | 5,3(2) s | β− | 149Pr | (3/2−) | ||
| 150Ce | 58 | 92 | 149,93041(5) | 4,0(6) s | β− | 150Pr | 0+ | ||
| 151Ce | 58 | 93 | 150,93398(11) | 1,02(6) s | β− | 151Pr | 3/2− | ||
| 152Ce | 58 | 94 | 151,93654(21) | 1,4(2) s | β− | 152Pr | 0+ | ||
| 153Ce | 58 | 95 | 152,94058(43) | 500 ms | β− | 153Pr | 3/2− | ||
| 154Ce | 58 | 96 | 153,94342(54) | 300 ms | β− | 154Pr | 0+ | ||
| 155Ce | 58 | 97 | 154,94804(64) | 200 ms | β− | 155Pr | 5/2− | ||
| 156Ce | 58 | 98 | 155,95126(64) | 150 ms | β− | 156Pr | 0+ | ||
| 157Ce | 58 | 99 | 156,95634(75) | 50 ms | β− | 157Pr | 7/2+ | ||
Overzicht van isotopen per element
[bewerken | brontekst bewerken]| 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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