Isotope van mendelevium
Die chemiese element mendelevium (Md), met ’n atoommassa van ongeveer 258 u, het geen stabiele isotope nie en word dus as ’n radioaktiewe element geklassifiseer. Die 17 isotope is onstabiel en het ’n relatief kort halfleeftyd (die meeste minder as ’n uur).
In die natuur kom geen mendelevium voor nie; alle isotope is sinteties in ’n laboratorium berei. Die eerste sintetiese isotoop was 256Md, in 1955.
Die kortslewende isotoop van mendelevium is 245Md, met ’n halfleeftyd van ongeveer 0,9 millisekondes. Die langslewende een is 258Md, met ’n halfleeftyd van 51,3 dae.
Oorsig
wysig| Nuklied | Z (p) | N (n) | Isotopiese massa (u) | Halfleeftyd | Radioaktiewe verval | VP | Kernspin |
|---|---|---|---|---|---|---|---|
| Opwekkingsenergie | |||||||
| 245Md | 101 | 144 | 245,08083(35) | 0,90(25) ms | SS | (1/2-) | |
| α (selde) | 241Es | ||||||
| 245mMd | 200(100) keV | 400(200) ms | α | 241Es | (7/2+) | ||
| β+ (selde) | 245Fm | ||||||
| 246Md | 101 | 145 | 246,08189(35) | 1,0(4) s | α | 242Es | |
| β+ (selde) | 246Fm | ||||||
| 247Md | 101 | 146 | 247,08164(35) | 1,12(22) s | SS | 1/2- | |
| α (selde) | 243Es | ||||||
| 247mMd | ± 0,2 s | α (99,99%) | 243Es | ||||
| SS (10−4%) | |||||||
| 248Md | 101 | 147 | 248,08282(26) | 7(3) s | β+ (80%) | 248Fm | |
| α (20%) | 244Es | ||||||
| β+, SS (0,05%) | |||||||
| 249Md | 101 | 148 | 249,08301(24) | 24(4) s | α (60%) | 245Es | (7/2-) |
| β+ (40%) | 249Fm | ||||||
| 249mMd | 100(100) keV | 1,9(9) s | (1/2-) | ||||
| 250Md | 101 | 149 | 250,08442(32) | 52(6) s | β+ (93%) | 250Fm | |
| α (7%) | 246Es | ||||||
| β+, SS (0,02%) | |||||||
| 251Md | 101 | 150 | 251,08484(22) | 4,0(5) min. | β+ (90%) | 251Fm | 7/2- |
| α (10%) | 247Es | ||||||
| 252Md | 101 | 151 | 252,08656(21) | 2,3(8) min. | β+ (50%) | 252Fm | |
| α (50%) | 248Es | ||||||
| 253Md | 101 | 152 | 253,08728(22) | 12(8) min. | β+ | 253Fm | 7/2- |
| α | 249Es | ||||||
| 254Md | 101 | 153 | 254,08966(11) | 10(3) min. | β+ | 254Fm | (0-) |
| α (selde) | 250Es | ||||||
| 254mMd | 50(100) keV | 28(8) min. | β+ | 254Fm | (3-) | ||
| α (selde) | 250Es | ||||||
| 255Md | 101 | 154 | 255,091083(7) | 27(2) min. | β+ (92%) | 255Fm | (7/2-) |
| α (8%) | 251Es | ||||||
| SS (0,15%) | |||||||
| 256Md | 101 | 155 | 256,09406(6) | 77(2) min. | β+ (89%) | 256Fm | (1-) |
| α (11%) | 252Es | ||||||
| 257Md | 101 | 156 | 257,095541(3) | 5,52(5) uur | EV (84,8%) | 257Fm | (7/2-) |
| α (15,2%) | 253Es | ||||||
| SS (1%) | |||||||
| 258Md | 101 | 157 | 258,098431(5) | 51,5(3) dae | α (99,99%) | 254Es | (8-) |
| β− (0,0015%) | 258No | ||||||
| β+ (0,0015%) | 258Fm | ||||||
| 258mMd | 0(200) keV | 57,0(9) min. | EV (70%) | 258Fm | 1- | ||
| SS (20%) | |||||||
| β− (10%) | 258No | ||||||
| α (1,2%) | 254Es | ||||||
| 259Md | 101 | 158 | 259,10051(22) | 1,60(6) uur | SS (98,7%) | 7/2- | |
| α (1,3%) | 255Es | ||||||
| 260Md | 101 | 159 | 260,10365(34) | 27,8(8) dae | SS (85%) | ||
| α (5%) | 256Es | ||||||
| EV (5%) | 260Fm | ||||||
| β− (3,5%) | 260No | ||||||
| 261Md | 101 | 160 | 261,10572(70) | 40 min. | 7/2- | ||
| 262Md | 101 | 161 | 262,10887(63) | 3 min. | |||
Isotope per element
wysig| 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 |
Bronne
wysig- R.B. Firestone, S.Y. Frank Chu & C.M. Baglin (1999) - Table of Isotopes (aanlyn weergawe van die CD-ROM)
- 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
- 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
- M.E. Wieser (2006) - Atomic weights of the elements 2005 (IUPAC Technical Report), Pure and Applied Chemistry, 78 (11), pp. 2051–2066
- David R. Lide (2004) - CRC Handbook of Chemistry and Physics (85ste uitg.), hoofstuk 11, CRC Press - ISBN 978-0849304859
Hierdie artikel is vertaal uit die Nederlandse Wikipedia
