Isotopen van mendelevium
Het chemisch element mendelevium (Md), met een atoommassa van ongeveer 258 u, bezit geen stabiele isotopen en wordt dus geclassificeerd als radioactief element. De 17 radio-isotopen zijn onstabiel en hebben een relatief korte halfwaardetijd (de meeste minder dan een uur).
In de natuur komt geen mendelevium voor: alle isotopen zijn synthetisch bereid in een laboratorium. De eerste synthetische isotoop was 256Md, in 1955.
De kortstlevende isotoop van mendelevium is 245Md, met een halfwaardetijd van ongeveer 0,9 milliseconden. De langstlevende is 258Md, met een halfwaardetijd van 51,5 dagen.
Overzicht bewerken
Nuclide | Z (p) | N (n) | Isotopische massa (u) | Halveringstijd | Radioactief verval | Kernspin |
---|---|---|---|---|---|---|
Excitatie-energie | ||||||
245Md | 101 | 144 | 245,08083(35) | 0,90(25) ms | SS | (1/2−) |
245101Md → 24199Es + 42α (zelden) | ||||||
245mMd | 200(100) keV | 400(200) ms | 245m101Md → 24199Es + 42α | (7/2+) | ||
245101Md → 245100Fm + 01e+ + νe (zelden) | ||||||
246Md | 101 | 145 | 246,08189(35) | 1,0(4) s | 246101Md → 24299Es + 42α | |
246101Md → 246100Fm + 01e+ + νe (zelden) | ||||||
247Md | 101 | 146 | 247,08164(35) | 1,12(22) s | SS | 1/2− |
247101Md → 24399Es + 42α (zelden) | ||||||
247mMd | ± 0,2 s | 247m101Md → 24399Es + 42α (99,99%) | ||||
SS (10−4%) | ||||||
248Md | 101 | 147 | 248,08282(26) | 7(3) s | 248101Md → 248100Fm + 01e+ + νe (80%) | |
248101Md → 24499Es + 42α (20%) | ||||||
SS (0,05%) | ||||||
249Md | 101 | 148 | 249,08301(24) | 24(4) s | 249101Md → 24599Es + 42α (60%) | (7/2−) |
249101Md → 249100Fm + 01e+ + νe (40%) | ||||||
249mMd | 100(100) keV | 1,9(9) s | (1/2−) | |||
250Md | 101 | 149 | 250,08442(32) | 52(6) s | 250101Md → 250100Fm + 01e+ + νe (93%) | |
250101Md → 24699Es + 42α (7%) | ||||||
SS (0,02%) | ||||||
251Md | 101 | 150 | 251,08484(22) | 4,0(5) min | 251101Md → 251100Fm + 01e+ + νe (90%) | 7/2− |
251101Md → 24799Es + 42α (10%) | ||||||
252Md | 101 | 151 | 252,08656(21) | 2,3(8) min | 252101Md → 252100Fm + 01e+ + νe (50%) | |
252101Md → 24899Es + 42α (50%) | ||||||
253Md | 101 | 152 | 253,08728(22) | 12(8) min | 253101Md → 253100Fm + 01e+ + νe | 7/2− |
253101Md → 24999Es + 42α | ||||||
254Md | 101 | 153 | 254,08966(11) | 10(3) min | 254101Md → 254100Fm + 01e+ + νe | (0−) |
254101Md → 25099Es + 42α (zelden) | ||||||
254mMd | 50(100) keV | 28(8) min | 254101Md → 254100Fm + 01e+ + νe | (3−) | ||
254101Md → 25099Es + 42α (zelden) | ||||||
255Md | 101 | 154 | 255,091083(7) | 27(2) min | 255101Md → 255100Fm + 01e+ + νe (92%) | (7/2−) |
255101Md → 25199Es + 42α (8%) | ||||||
SS (0,15%) | ||||||
256Md | 101 | 155 | 256,09406(6) | 77(2) min | 256101Md → 256100Fm + 01e+ + νe (89%) | (1−) |
256101Md → 25299Es + 42α (11%) | ||||||
257Md | 101 | 156 | 257,095541(3) | 5,52(5) uur | 257101Md + 0−1e → 257100Fm + νe (84,8%) | (7/2−) |
257101Md → 25399Es + 42α (15,2%) | ||||||
SS (1%) | ||||||
258Md | 101 | 157 | 258,098431(5) | 51,5(3) dagen | 258101Md → 25499Es + 42α (99,99%) | (8−) |
258101Md → 258102No + 0−1e + νe (0,0015%) | ||||||
258101Md → 258100Fm + 01e+ + νe (0,0015%) | ||||||
258mMd | 0(200) keV | 57,0(9) min | 258101Md + 0−1e → 258100Fm + νe(70%) | 1− | ||
SS (20%) | ||||||
258101Md → 258102No + 0−1e + νe (10%) | ||||||
258101Md → 25499Es + 42α (1,2%) | ||||||
259Md | 101 | 158 | 259,10051(22) | 1,60(6) uur | SS (98,7%) | 7/2− |
259101Md → 25599Es + 42α (1,3%) | ||||||
260Md | 101 | 159 | 260,10365(34) | 27,8(8) dagen | SS (85%) | |
260101Md → 25699Es + 42α (5%) | ||||||
260101Md + 0−1e → 260100Fm + νe(5%) | ||||||
260101Md → 260102No + 0−1e + νe (3,5%) | ||||||
261Md | 101 | 160 | 261,10572(70) | 40 min | 7/2− | |
262Md | 101 | 161 | 262,10887(63) | 3 min |
Overzicht van isotopen per element 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
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