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The isotopic abundance describes the relative number of atoms of a given isotope in a mixture of isotopes of a given chemical element, expressed as a fraction of all the atoms of that element [1].
Status: 2013; published in March 2016 [3].
The natural isotopic abundances given correspond to the current values from the CIAAW.
The table provides general information about each element, such as atomic number (Z), element symbol, and name.
Column 4 - A:
A is the mass number of the respective isotope, ie the sum of the protons and neutrons in the nucleus.
Column 5 to 7:
Columns five through seven list the actual isotopic abundances. For some elements, these are given in intervals (I1 to I2), since the terrestrial occurrences are subject to natural fluctuations. Elements with an isotope abundance = 1 (corresponding to 100 %) are mononuclide elements, ie the occurrences are composed of only one isotope. A dash means the element is not naturally occurring.
Column 8:
a - Geological materials are known in which the chemical element in question has an isotopic composition outside the limits for otherwise (normal) occurring materials. The difference between the atomic weight of the element of these materials and those given in the table may exceed the uncertainties stated.
b - Different isotopic compositions may occur in commercially available preparations due to unknown or accidental isotopic fractionation; the deviation from the value given here can be significant.
c - The range of isotopic composition on Earth varies and prevents accurate reporting. However, the reported value should be applicable to ordinary samples.
| Z | Symbol | Element | A | Composition | I1 | I2 | Notes |
|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
| 1 | H | Hydrogen | 1 | () | 0.99972 | 0.99999 | b |
| 2 | () | 0.00001 | 0.00028 | ||||
| 2 | He | Helium | 3 | 0.000002(2) | a, c | ||
| 4 | 0.999998(2) | ||||||
| 3 | Li | Lithium | 6 | () | 0.019 | 0.078 | b |
| 7 | () | 0.922 | 0.981 | ||||
| 4 | Be | Beryllium | 9 | 1 | |||
| 5 | B | Boron | 10 | () | 0.189 | 0.204 | b |
| 11 | () | 0.796 | 0.811 | ||||
| 6 | C | Carbon | 12 | () | 0.9884 | 0.9904 | |
| 13 | () | 0.0096 | 0.0116 | ||||
| 7 | N | Nitrogen | 14 | () | 0.99578 | 0.99663 | |
| 15 | () | 0.00337 | 0.00422 | ||||
| 8 | O | Oxygen | 16 | () | 0.99738 | 0.99776 | |
| 17 | () | 0.000367 | 0.000400 | ||||
| 18 | () | 0.00187 | 0.00222 | ||||
| 9 | F | Fluorine | 19 | 1 | |||
| 10 | Ne | Neon | 20 | 0.9048(3) | a, b | ||
| 21 | 0.0027(1) | ||||||
| 22 | 0.0925(3) | ||||||
| 11 | Na | Sodium | 23 | 1 | |||
| 12 | Mg | Magnesium | 24 | () | 0.7888 | 0.7905 | |
| 25 | () | 0.09988 | 0.10034 | ||||
| 26 | () | 0.1096 | 0.1109 | ||||
| 13 | Al | Aluminium | 27 | 1 | |||
| 14 | Si | Silicon | 28 | () | 0.92191 | 0.92318 | |
| 29 | () | 0.04645 | 0.04699 | ||||
| 30 | () | 0.03037 | 0.03110 | ||||
| 15 | P | Phosphorus | 31 | 1 | |||
| 16 | S | Sulfur | 32 | () | 0.9441 | 0.9529 | |
| 33 | () | 0.00729 | 0.00797 | ||||
| 34 | () | 0.0396 | 0.0477 | ||||
| 36 | () | 0.000129 | 0.000187 | ||||
| 17 | Cl | Chlorine | 35 | () | 0.755 | 0.761 | b |
| 37 | () | 0.239 | 0.245 | ||||
| 18 | Ar | Argon | 36 | 0.003336(210) | a, c | ||
| 38 | 0.000629(70) | ||||||
| 40 | 0.996035(250) | ||||||
| 19 | K | Potassium | 39 | 0.932581(44) | |||
| 40 | 0.000117(1) | ||||||
| 41 | 0.067302(44) | ||||||
| 20 | Ca | Calcium | 40 | 0.96941(156) | a | ||
| 42 | 0.00647(23) | ||||||
| 43 | 0.00135(10) | ||||||
| 44 | 0.02086(110) | ||||||
| 46 | 0.00004(3) | ||||||
| 48 | 0.00187(21) | ||||||
| 21 | Sc | Scandium | 45 | 1 | |||
| 22 | Ti | Titan | 46 | 0.0825(3) | |||
| 47 | 0.0744(2) | ||||||
| 48 | 0.7372(3) | ||||||
| 49 | 0.0541(2) | ||||||
| 50 | 0.0518(2) | ||||||
| 23 | V | Vanadium | 50 | 0.000250(10) | |||
| 51 | 0.99750(10) | ||||||
| 24 | Cr | Chrome | 50 | 0.04345(13) | |||
| 52 | 0.83789(18) | ||||||
| 53 | 0.09501(17) | ||||||
| 54 | 0.02365(7) | ||||||
| 25 | Mn | Manganese | 55 | 1 | |||
| 26 | Fe | Iron | 54 | 0.05845(105) | |||
| 56 | 0.91754(106) | ||||||
| 57 | 0.02119(29) | ||||||
| 58 | 0.00282(12) | ||||||
| 27 | Co | Cobalt | 59 | 1 | |||
| 28 | Ni | Nickel | 58 | 0.680769(190) | c | ||
| 60 | 0.262231(150) | ||||||
| 61 | 0.011399(13) | ||||||
| 62 | 0.036345(40) | ||||||
| 64 | 0.009256(19) | ||||||
| 29 | Cu | Copper | 63 | 0.6915(15) | c | ||
| 65 | 0.3085(15) | ||||||
| 30 | Zn | Zinc | 64 | 0.4917(75) | c | ||
| 66 | 0.2773(98) | ||||||
| 67 | 0.0404(16) | ||||||
| 68 | 0.1845(63) | ||||||
| 70 | 0.0061(10) | ||||||
| 31 | Ga | Gallium | 69 | 0.60108(50) | |||
| 71 | 0.39892(50) | ||||||
| 32 | Ge | Germanium | 70 | 0.2052(19) | |||
| 72 | 0.2745(15) | ||||||
| 73 | 0.0776(8) | ||||||
| 74 | 0.3652(12) | ||||||
| 76 | 0.0775(12) | ||||||
| 33 | As | Arsenic | 75 | 1 | |||
| 34 | Se | Selenium | 74 | 0.0086(3) | c | ||
| 76 | 0.0923(7) | ||||||
| 77 | 0.0760(7) | ||||||
| 78 | 0.2369(22) | ||||||
| 80 | 0.4980(36) | ||||||
| 82 | 0.0882(15) | ||||||
| 35 | Br | Bromine | 79 | () | 0.505 | 0.508 | |
| 81 | () | 0.492 | 0.495 | ||||
| 36 | Kr | Krypton | 78 | 0.00355(3) | a, b | ||
| 80 | 0.02286(10) | ||||||
| 82 | 0.11593(31) | ||||||
| 83 | 0.11500(19) | ||||||
| 84 | 0.56987(15) | ||||||
| 86 | 0.17279(41) | ||||||
| 37 | Rb | Rubidium | 85 | 0.7217(2) | a | ||
| 87 | 0.2783(2) | ||||||
| 38 | Sr | Strontium | 84 | 0.0056(2) | a, c | ||
| 86 | 0.0986(20) | ||||||
| 87 | 0.0700(20) | ||||||
| 88 | 0.8258(35) | ||||||
| 39 | Y | Yttrium | 89 | 1 | |||
| 40 | Zr | Zirconium | 90 | 0.5145(4) | a | ||
| 91 | 0.1122(5) | ||||||
| 92 | 0.1715(3) | ||||||
| 94 | 0.1738(4) | ||||||
| 96 | 0.0280(2) | ||||||
| 41 | Nb | Niobium | 93 | 1 | |||
| 42 | Mo | Molybdenum | 92 | 0.14649(106) | a | ||
| 94 | 0.09187(33) | ||||||
| 95 | 0.15873(30) | ||||||
| 96 | 0.16673(8) | ||||||
| 97 | 0.09582(15) | ||||||
| 98 | 0.24292(80) | ||||||
| 100 | 0.09744(65) | ||||||
| 43 | Tc | Technetium | [98] | - | |||
| 44 | Ru | Ruthenium | 96 | 0.0554(14) | a | ||
| 98 | 0.0187(3) | ||||||
| 99 | 0.1276(14) | ||||||
| 100 | 0.1260(7) | ||||||
| 101 | 0.1706(2) | ||||||
| 102 | 0.3155(14) | ||||||
| 104 | 0.1862(27) | ||||||
| 45 | Rh | Rhodium | 103 | 1 | |||
| 46 | Pd | Palladium | 102 | 0.0102(1) | a | ||
| 104 | 0.1114(8) | ||||||
| 105 | 0.2233(8) | ||||||
| 106 | 0.2733(3) | ||||||
| 108 | 0.2646(9) | ||||||
| 110 | 0.1172(9) | ||||||
| 47 | Ag | Silver | 107 | 0.51839(8) | a | ||
| 109 | 0.48161(8) | ||||||
| 48 | Cd | Cadmium | 106 | 0.01245(22) | a | ||
| 108 | 0.00888(11) | ||||||
| 110 | 0.12470(61) | ||||||
| 111 | 0.12795(12) | ||||||
| 112 | 0.24109(7) | ||||||
| 113 | 0.12227(7) | ||||||
| 114 | 0.28754(81) | ||||||
| 116 | 0.07512(54) | ||||||
| 49 | In | Indium | 113 | 0.04281(52) | |||
| 115 | 0.95719(52) | ||||||
| 50 | Sn | Tin | 112 | 0.0097(1) | a | ||
| 114 | 0.0066(1) | ||||||
| 115 | 0.0034(1) | ||||||
| 116 | 0.1454(9) | ||||||
| 117 | 0.0768(7) | ||||||
| 118 | 0.2422(9) | ||||||
| 119 | 0.0859(4) | ||||||
| 120 | 0.3258(9) | ||||||
| 122 | 0.0463(3) | ||||||
| 124 | 0.0579(5) | ||||||
| 51 | Sb | Antimony | 121 | 0.5721(5) | a | ||
| 123 | 0.4279(5) | ||||||
| 52 | Te | Tellurium | 120 | 0.0009(1) | a | ||
| 122 | 0.0255(12) | ||||||
| 123 | 0.0089(3) | ||||||
| 124 | 0.0474(14) | ||||||
| 125 | 0.0707(15) | ||||||
| 126 | 0.1884(25) | ||||||
| 128 | 0.3174(8) | ||||||
| 130 | 0.3408(62) | ||||||
| 53 | I | Iodine | 127 | 1 | |||
| 54 | Xe | Xenon | 124 | 0.00095(5) | a, b | ||
| 126 | 0.00089(3) | ||||||
| 128 | 0.01910(13) | ||||||
| 129 | 0.26401(138) | ||||||
| 130 | 0.04071(22) | ||||||
| 131 | 0.21232(51) | ||||||
| 132 | 0.26909(55) | ||||||
| 134 | 0.10436(35) | ||||||
| 136 | 0.08857(72) | ||||||
| 55 | Cs | Caesium | 133 | 1 | |||
| 56 | Ba | Barium | 130 | 0.0011(1) | |||
| 132 | 0.0010(1) | ||||||
| 134 | 0.0242(15) | ||||||
| 135 | 0.0659(10) | ||||||
| 136 | 0.0785(24) | ||||||
| 137 | 0.1123(23) | ||||||
| 138 | 0.7170(29) | ||||||
| 57 | La | Lanthanum | 138 | 0.0008881(71) | a | ||
| 139 | 0.9991119(71) | ||||||
| 58 | Ce | Cerium | 136 | 0.00186(2) | a | ||
| 138 | 0.00251(2) | ||||||
| 140 | 0.88449(51) | ||||||
| 142 | 0.11114(51) | ||||||
| 59 | Pr | Praseodymium | 141 | 1 | |||
| 60 | Nd | Neodymium | 142 | 0.27153(40) | a | ||
| 143 | 0.12173(26) | ||||||
| 144 | 0.23798(19) | ||||||
| 145 | 0.08293(12) | ||||||
| 146 | 0.17189(32) | ||||||
| 148 | 0.05756(21) | ||||||
| 150 | 0.05638(28) | ||||||
| 61 | Pm | Promethium | [145] | - | |||
| 62 | Sm | Samarium | 144 | 0.0308(4) | a | ||
| 147 | 0.1500(14) | ||||||
| 148 | 0.1125(9) | ||||||
| 149 | 0.1382(10) | ||||||
| 150 | 0.0737(9) | ||||||
| 152 | 0.2674(9) | ||||||
| 154 | 0.2274(14) | ||||||
| 63 | Eu | Europium | 151 | 0.4781(6) | a | ||
| 153 | 0.5219(6) | ||||||
| 64 | Gd | Gadolinium | 152 | 0.0020(3) | a | ||
| 154 | 0.0218(2) | ||||||
| 155 | 0.1480(9) | ||||||
| 156 | 0.2047(3) | ||||||
| 157 | 0.1565(4) | ||||||
| 158 | 0.2484(8) | ||||||
| 160 | 0.2186(3) | ||||||
| 65 | Tb | Terbium | 159 | 1 | |||
| 66 | Dy | Dysprosium | 156 | 0.00056(3) | a | ||
| 158 | 0.00095(3) | ||||||
| 160 | 0.02329(18) | ||||||
| 161 | 0.18889(42) | ||||||
| 162 | 0.25475(36) | ||||||
| 163 | 0.24896(42) | ||||||
| 164 | 0.28260(54) | ||||||
| 67 | Ho | Holmium | 165 | 1 | |||
| 68 | Er | Erbium | 162 | 0.00139(5) | a | ||
| 164 | 0.01601(3) | ||||||
| 166 | 0.33503(36) | ||||||
| 167 | 0.22869(9) | ||||||
| 168 | 0.26978(18) | ||||||
| 170 | 0.14910(36) | ||||||
| 69 | Tm | Thulium | 169 | 1 | |||
| 70 | Yb | Ytterbium | 168 | 0.00126(1) | a | ||
| 170 | 0.03023(2) | ||||||
| 171 | 0.14216(7) | ||||||
| 172 | 0.21754(10) | ||||||
| 173 | 0.16098(9) | ||||||
| 174 | 0.31896(26) | ||||||
| 176 | 0.12887(30) | ||||||
| 71 | Lu | Lutetium | 175 | 0.97401(13) | a | ||
| 176 | 0.02599(13) | ||||||
| 72 | Hf | Hafnium | 174 | 0.0016(12) | |||
| 176 | 0.0526(70) | ||||||
| 177 | 0.1860(16) | ||||||
| 178 | 0.2728(28) | ||||||
| 179 | 0.1362(11) | ||||||
| 180 | 0.3508(33) | ||||||
| 73 | Ta | Tantalum | 180 | 0.0001201(32) | |||
| 181 | 0.9998799(32) | ||||||
| 74 | W | Tungsten | 180 | 0.0012(1) | |||
| 182 | 0.2650(16) | ||||||
| 183 | 0.1431(4) | ||||||
| 184 | 0.3064(2) | ||||||
| 186 | 0.2843(19) | ||||||
| 75 | Re | Rhenium | 185 | 0.3740(5) | |||
| 187 | 0.6260(5) | ||||||
| 76 | Os | Osmium | 184 | 0.0002(2) | a | ||
| 186 | 0.0159(64) | ||||||
| 187 | 0.0196(17) | ||||||
| 188 | 0.1324(27) | ||||||
| 189 | 0.1615(23) | ||||||
| 190 | 0.2626(20) | ||||||
| 192 | 0.4078(32) | ||||||
| 77 | Ir | Iridium | 191 | 0.373(2) | |||
| 193 | 0.627(2) | ||||||
| 78 | Pt | Platinum | 190 | 0.00012(2) | |||
| 192 | 0.00782(24) | ||||||
| 194 | 0.32864(410) | ||||||
| 195 | 0.33775(240) | ||||||
| 196 | 0.25211(340) | ||||||
| 198 | 0.07356(130) | ||||||
| 79 | Au | Gold | 197 | 1 | |||
| 80 | Hg | Mercury | 196 | 0.0015(1) | |||
| 198 | 0.1004(3) | ||||||
| 199 | 0.1694(12) | ||||||
| 200 | 0.2314(9) | ||||||
| 201 | 0.1317(9) | ||||||
| 202 | 0.2974(13) | ||||||
| 204 | 0.0682(4) | ||||||
| 81 | Tl | Thallium | 203 | () | 0.2944 | 0.2959 | |
| 205 | () | 0.7041 | 0.7056 | ||||
| 82 | Pb | Lead | 204 | 0.014(6) | a, c | ||
| 206 | 0.241(30) | ||||||
| 207 | 0.221(50) | ||||||
| 208 | 0.524(70) | ||||||
| 83 | Bi | Bismuth | 209 | 1 | |||
| 84 | Po | Polonium | [209] | - | |||
| 85 | At | Astatine | [210] | - | |||
| 86 | Rn | Radon | [222] | - | |||
| 87 | Fr | Francium | [223] | - | |||
| 88 | Ra | Radium | [226] | - | |||
| 89 | Ac | Actinium | [227] | - | |||
| 90 | Th | Thorium | 230 | 0.0002(2) | |||
| 232 | 0.9998(2) | ||||||
| 91 | Pa | Protactinium | 231 | 1 | |||
| 92 | U | Uranium | 234 | 0.000054(5) | a, b | ||
| 235 | 0.007204(6) | ||||||
| 238 | 0.992742(10) |
[1] - Isotopic abundance.
IUPAC Gold Book, DOI 10.1351/goldbook.I03332.
[2] - IUPAC:
Standard Atomic Weight of Ytterbium Revised.
Chemistry International, (2015), DOI 10.1515/ci-2015-0512.
[3] - Juris Meija, Tyler B. Coplen, Michael Berglund, Willi A. Brand, Paul De Bičvre, Manfred Gröning, Norman E. Holden, Johanna Irrgeher, Robert D. Loss, Thomas Walczyk, Thomas Prohaska:
Isotopic Compositions of the Elements 2013 (IUPAC Technical Report).
Pure and Applied Chemistry, (2016), DOI 10.1515/pac-2015-0503.
Last update: 2022-12-16
Perma link: https://www.chemlin.org/chemical-elements/isotopic-abundances.php
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