Isotope van neptunium
Neptunium (Np) is ’n kunsmatige chemiese element en ’n standaardmassa kan dus nie bepaal word nie. Dit het geen stabiele isotope nie en word dus as radioaktief geklassifiseer. Die meeste van die 20 isotope het ’n relatief kort halfleeftyd.
In die natuur kom net spoorhoeveelhede neptunium voor; die meeste isotope is sinteties in ’n laboratorium berei. Die eerste sintetiese isotoop was 239Np, in 1940. Dit is geskep deur 238U met neutrone te bestook om 239U te vervaardig, wat toe betaverval ondergaan het tot 239Np.
Die stabielste neptuniumisotope is 237Np (met ’n halfleeftyd van 2,14 miljoen jaar), 236Np (154 000 jaar) en 235Np (396,1 dae). Alle ander isotope het ’n halfleeftyd van minder as 4,5 dae; die meeste s’n is korter as 50 minute.
Oorsig
[wysig | wysig bron]| Nuklied | Z (p) | N (n) | Isotopiese massa (u) | Halfleeftyd | Radioaktiewe verval | VP | Kernspin |
|---|---|---|---|---|---|---|---|
| Opwekkingsenergie | |||||||
| 225Np | 93 | 132 | 225,03391(8) | 3# ms [>2 µs] | α | 221Pa | 9/2−# |
| 226Np | 93 | 133 | 226,03515(10)# | 35(10) ms | α | 222Pa | |
| 227Np | 93 | 134 | 227,03496(8) | 510(60) ms | α (99,95%) | 223Pa | 5/2−# |
| β+ (,05%) | 227U | ||||||
| 228Np | 93 | 135 | 228,03618(21)# | 61,4(14) s | β+ (59%) | 228U | |
| α (41%) | 224Pa | ||||||
| β+, SS (,012%) | (verskeie) | ||||||
| 229Np | 93 | 136 | 229,03626(9) | 4,0(2) min. | α (51%) | 225Pa | 5/2+# |
| β+ (49%) | 229U | ||||||
| 230Np | 93 | 137 | 230,03783(6) | 4,6(3) min. | β+ (97%) | 230U | |
| α (3%) | 226Pa | ||||||
| 231Np | 93 | 138 | 231,03825(5) | 48m8(2) min | β+ (98%) | 231U | (5/2)(+#) |
| α (2%) | 227Pa | ||||||
| 232Np | 93 | 139 | 232,04011(11)# | 14,7(3) min. | β+ (99,99%) | 232U | (4+) |
| α (.003%) | 228Pa | ||||||
| 233Np | 93 | 140 | 233,04074(5) | 36,2(1) min | β+ (99,99%) | 233U | (5/2+) |
| α (,001%) | 229Pa | ||||||
| 234Np | 93 | 141 | 234,042895(9) | 4,4(1) d | β+ | 234U | (0+) |
| 235Np | 93 | 142 | 235,0440633(21) | 396,1(12) d | EV | 235U | 5/2+ |
| α (,0026%) | 231Pa | ||||||
| 236Np[nota 1] | 93 | 143 | 236,04657(5) | 1,54(6)×105 j | EV (87,3%) | 236U | (6−) |
| β− (12,5%) | 236Pu | ||||||
| α (,16%) | 232Pa | ||||||
| 236mNp | 60(50) keV | 22,5(4) u | EV (52%) | 236U | 1 | ||
| β− (48%) | 236Pu | ||||||
| 237Np[nota 2] | 93 | 144 | 237,0481734(20) | 2,144(7)×106 y | α | 233Pa | 5/2+ |
| SS (2×10−10%) | (verskeie) | ||||||
| TV (4×10−12%) | 207Tl 30Mg | ||||||
| 238Np | 93 | 145 | 238,0509464(20) | 2,117(2) d | β− | 238Pu | 2+ |
| 238mNp | 2300(200)# keV | 112(39) ns | |||||
| 239Np | 93 | 146 | 239,0529390(22) | 2,356(3) d | β− | 239Pu | 5/2+ |
| 240Np | 93 | 147 | 240,056162(16) | 61,9(2) min. | β− | 240Pu | (5+) |
| 240mNp | 20(15) keV | 7,22(2) min. | β− (99,89%) | 240Pu | 1(+) | ||
| IO (,11%) | 240Np | ||||||
| 241Np | 93 | 148 | 241,05825(8) | 13,9(2) min. | β− | 241Pu | (5/2+) |
| 242Np | 93 | 149 | 242,06164(21) | 2,2(2) min. | β− | 242Pu | (1+) |
| 242mNp | 0(50)# keV | 5,5(1) min. | 6+# | ||||
| 243Np | 93 | 150 | 243,06428(3)# | 1,85(15) min. | β− | 243Pu | (5/2−) |
| 244Np | 93 | 151 | 244,06785(32)# | 2,29(16) min. | β− | 244Pu | (7−) |
Notas
[wysig | wysig bron]- Waardes wat met # gemerk is, is nie slegs afgelei van eksperimentele data nie, maar minstens gedeeltelik van sistematiese neigings.
- Onsekerhede word aangedui in verkorte vorm tussen hakies ná die ooreenstemmende laaste syfers.
Isotope per element
[wysig | wysig bron]| 1H | 2He | 3Li | 4Be | 5B | 6C | 7N | 8O | 9F | 10Ne | 11Na | 12Mg | 13Al | 14Si | 15P | 16S | 17Cl | 18Ar | 19K | |
| 20Ca | 21Sc | 22Ti | 23V | 24Cr | 25Mn | 26Fe | 27Co | 28Ni | 29Cu | 30Zn | 31Ga | 32Ge | 33As | 34Se | 35Br | 36Kr | 37Rb | 38Sr | 39Y |
| 40Zr | 41Nb | 42Mo | 43Tc | 44Ru | 45Rh | 46Pd | 47Ag | 48Cd | 49In | 50Sn | 51Sb | 52Te | 53I | 54Xe | 55Cs | 56Ba | 57La | 58Ce | 59Pr |
| 60Nd | 61Pm | 62Sm | 63Eu | 64Gd | 65Tb | 66Dy | 67Ho | 68Er | 69Tm | 70Yb | 71Lu | 72Hf | 73Ta | 74W | 75Re | 76Os | 77Ir | 78Pt | 79Au |
| 80Hg | 81Tl | 82Pb | 83Bi | 84Po | 85At | 86Rn | 87Fr | 88Ra | 89Ac | 90Th | 91Pa | 92U | 93Np | 94Pu | 95Am | 96Cm | 97Bk | 98Cf | 99Es |
| 100Fm | 101Md | 102No | 103Lr | 104Rf | 105Db | 106Sg | 107Bh | 108Hs | 109Mt | 110Ds | 111Rg | 112Cn | 113Nh | 114Fl | 115Mc | 116Lv | 117Ts | 118Og |