Naturally occurring

tungsten Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolat ...

(₇₄W) consists of five

isotope Isotopes are two or more types of atoms that have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to the same chemical element), and that differ in nucleon numbers (mass numbers) ...

s. Four are considered

stable A stable is a building in which livestock, especially horses, are kept. It most commonly means a building that is divided into separate stalls for individual animals and livestock. There are many different types of stables in use today; the ...

(¹⁸²W, ¹⁸³W, ¹⁸⁴W, and ¹⁸⁶W) and one is slightly

radioactive Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is consid ...

, ¹⁸⁰W, with an extremely long

half-life Half-life (symbol ) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable ato ...

of 1.8 ± 0.2 exayears (10¹⁸ years). On average, two

alpha decay Alpha decay or α-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus) and thereby transforms or 'decays' into a different atomic nucleus, with a mass number that is reduced by four and an atom ...

s of ¹⁸⁰W occur per gram of natural tungsten per year, so for most practical purposes, tungsten can be considered stable. Theoretically, all five can decay into isotopes of element 72 (hafnium) by alpha emission, but only ¹⁸⁰W has been observed to do so. The other naturally occurring isotopes have not been observed to decay (they are

observationally stable Stable nuclides are nuclides that are not radioactive and so (unlike radionuclides) do not spontaneously undergo radioactive decay. When such nuclides are referred to in relation to specific elements, they are usually termed stable isotopes. Th ...

), and lower bounds for their half lives have been established: :¹⁸²W, t_1/2 > 7.7×10²¹ years :¹⁸³W, t_1/2 > 4.1×10²¹ years :¹⁸⁴W, t_1/2 > 8.9×10²¹ years :¹⁸⁶W, t_1/2 > 8.2×10²¹ years Thirty-three artificial

radioisotope A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess nuclear energy, making it unstable. This excess energy can be used in one of three ways: emitted from the nucleus as gamma radiation; transferr ...

s of tungsten have been characterized with mass numbers ranging from 157 to 194, the most stable of which are ¹⁸¹W with a half-life of 121.2 days, ¹⁸⁵W with a half-life of 75.1 days, ¹⁸⁸W with a half-life of 69.4 days and ¹⁷⁸W with a half-life of 21.6 days. All of the remaining

isotopes have half-lives of less than 24 hours, and most of these have half-lives that are less than 8 minutes. Tungsten also has 11

meta state A nuclear isomer is a metastable state of an atomic nucleus, in which one or more nucleons (protons or neutrons) occupy higher energy levels than in the ground state of the same nucleus. "Metastable" describes nuclei whose excited states have ha ...

s with mass numbers of 158, 179, with 3, 180, with 2, 183, 185, 186, with 2, and 190, the most stable being ^179m1W (t_1/2 6.4 minutes).

List of isotopes

, - , ¹⁵⁸W , style="text-align:right" , 74 , style="text-align:right" , 84 , 157.97456(54)# , 1.37(17) ms , α , ¹⁵⁴Hf , 0+ , , , - , style="text-indent:1em" , ^158mW , colspan="3" style="text-indent:2em" , 1889(8) keV , 143(19) μs , , , 8+ , , , - , rowspan=2, ¹⁵⁹W , rowspan=2 style="text-align:right" , 74 , rowspan=2 style="text-align:right" , 85 , rowspan=2, 158.97292(43)# , rowspan=2, 8.2(7) ms , α (82%) , ¹⁵⁵Hf , rowspan=2, 7/2−# , rowspan=2, , rowspan=2, , - , β⁺ (18%) , ¹⁵⁹Ta , - , rowspan=2, ¹⁶⁰W , rowspan=2 style="text-align:right" , 74 , rowspan=2 style="text-align:right" , 86 , rowspan=2, 159.96848(22) , rowspan=2, 90(5) ms , α (87%) , ¹⁵⁶Hf , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , β⁺ (14%) , ¹⁶⁰Ta , - , rowspan=2, ¹⁶¹W , rowspan=2 style="text-align:right" , 74 , rowspan=2 style="text-align:right" , 87 , rowspan=2, 160.96736(21)# , rowspan=2, 409(16) ms , α (73%) , ¹⁵⁷Hf , rowspan=2, 7/2−# , rowspan=2, , rowspan=2, , - , β⁺ (23%) , ¹⁶¹Ta , - , rowspan=2, ¹⁶²W , rowspan=2 style="text-align:right" , 74 , rowspan=2 style="text-align:right" , 88 , rowspan=2, 161.963497(19) , rowspan=2, 1.36(7) s , β⁺ (53%) , ¹⁶²Ta , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , α (47%) , ¹⁵⁸Hf , - , rowspan=2, ¹⁶³W , rowspan=2 style="text-align:right" , 74 , rowspan=2 style="text-align:right" , 89 , rowspan=2, 162.96252(6) , rowspan=2, 2.8(2) s , β⁺ (59%) , ¹⁶³Ta , rowspan=2, 3/2−# , rowspan=2, , rowspan=2, , - , α (41%) , ¹⁵⁹Hf , - , rowspan=2, ¹⁶⁴W , rowspan=2 style="text-align:right" , 74 , rowspan=2 style="text-align:right" , 90 , rowspan=2, 163.958954(13) , rowspan=2, 6.3(2) s , β⁺ (97.4%) , ¹⁶⁴Ta , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , α (2.6%) , ¹⁶⁰Hf , - , rowspan=2, ¹⁶⁵W , rowspan=2 style="text-align:right" , 74 , rowspan=2 style="text-align:right" , 91 , rowspan=2, 164.958280(27) , rowspan=2, 5.1(5) s , β⁺ (99.8%) , ¹⁶⁵Ta , rowspan=2, 3/2−# , rowspan=2, , rowspan=2, , - , α (.2%) , ¹⁶¹Hf , - , rowspan=2, ¹⁶⁶W , rowspan=2 style="text-align:right" , 74 , rowspan=2 style="text-align:right" , 92 , rowspan=2, 165.955027(11) , rowspan=2, 19.2(6) s , β⁺ (99.96%) , ¹⁶⁶Ta , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , α (.035%) , ¹⁶²Hf , - , rowspan=2, ¹⁶⁷W , rowspan=2 style="text-align:right" , 74 , rowspan=2 style="text-align:right" , 93 , rowspan=2, 166.954816(21) , rowspan=2, 19.9(5) s , β⁺ (>99.9%) , ¹⁶⁷Ta , rowspan=2, 3/2−# , rowspan=2, , rowspan=2, , - , α (<.1%) , ¹⁶³Hf , - , rowspan=2, ¹⁶⁸W , rowspan=2 style="text-align:right" , 74 , rowspan=2 style="text-align:right" , 94 , rowspan=2, 167.951808(17) , rowspan=2, 51(2) s , β⁺ (99.99%) , ¹⁶⁸Ta , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , α (.0319%) , ¹⁶⁴Hf , - , ¹⁶⁹W , style="text-align:right" , 74 , style="text-align:right" , 95 , 168.951779(17) , 76(6) s , β⁺ , ¹⁶⁹Ta , (5/2−) , , , - , rowspan=2, ¹⁷⁰W , rowspan=2 style="text-align:right" , 74 , rowspan=2 style="text-align:right" , 96 , rowspan=2, 169.949228(16) , rowspan=2, 2.42(4) min , β⁺(99%) , ¹⁷⁰Ta , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , α (1%) , ¹⁶⁶Hf , - , ¹⁷¹W , style="text-align:right" , 74 , style="text-align:right" , 97 , 170.94945(3) , 2.38(4) min , β⁺ , ¹⁷¹Ta , (5/2−) , , , - , ¹⁷²W , style="text-align:right" , 74 , style="text-align:right" , 98 , 171.94729(3) , 6.6(9) min , β⁺ , ¹⁷²Ta , 0+ , , , - , ¹⁷³W , style="text-align:right" , 74 , style="text-align:right" , 99 , 172.94769(3) , 7.6(2) min , β⁺ , ¹⁷³Ta , 5/2− , , , - , ¹⁷⁴W , style="text-align:right" , 74 , style="text-align:right" , 100 , 173.94608(3) , 33.2(21) min , β⁺ , ¹⁷⁴Ta , 0+ , , , - , ¹⁷⁵W , style="text-align:right" , 74 , style="text-align:right" , 101 , 174.94672(3) , 35.2(6) min , β⁺ , ¹⁷⁵Ta , (1/2−) , , , - , ¹⁷⁶W , style="text-align:right" , 74 , style="text-align:right" , 102 , 175.94563(3) , 2.5(1) h , EC , ¹⁷⁶Ta , 0+ , , , - , ¹⁷⁷W , style="text-align:right" , 74 , style="text-align:right" , 103 , 176.94664(3) , 132(2) min , β⁺ , ¹⁷⁷Ta , 1/2− , , , - , ¹⁷⁸W , style="text-align:right" , 74 , style="text-align:right" , 104 , 177.945876(16) , 21.6(3) d , EC , ¹⁷⁸Ta , 0+ , , , - , ¹⁷⁹W , style="text-align:right" , 74 , style="text-align:right" , 105 , 178.947070(17) , 37.05(16) min , β⁺ , ¹⁷⁹Ta , (7/2)− , , , - , rowspan=2 style="text-indent:1em" , ^179m1W , rowspan=2 colspan="3" style="text-indent:2em" , 221.926(8) keV , rowspan=2, 6.40(7) min , IT (99.72%) , ¹⁷⁹W , rowspan=2, (1/2)− , rowspan=2, , rowspan=2, , - , β⁺ (.28%) , ¹⁷⁹Ta , - , style="text-indent:1em" , ^179m2W , colspan="3" style="text-indent:2em" , 1631.90(8) keV , 390(30) ns , , , (21/2+) , , , - , style="text-indent:1em" , ^179m3W , colspan="3" style="text-indent:2em" , 3348.45(16) keV , 750(80) ns , , , (35/2−) , , , - , ¹⁸⁰W Primordial

radionuclide A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess nuclear energy, making it unstable. This excess energy can be used in one of three ways: emitted from the nucleus as gamma radiation; transfer ...

, style="text-align:right" , 74 , style="text-align:right" , 106 , 179.946704(4) , 1.8(0.2)×10¹⁸ y , α , ¹⁷⁶Hf , 0+ , 0.0012(1) , , - , style="text-indent:1em" , ^180m1W , colspan="3" style="text-indent:2em" , 1529.04(3) keV , 5.47(9) ms , IT , ''¹⁸⁰W'' , 8− , , , - , style="text-indent:1em" , ^180m2W , colspan="3" style="text-indent:2em" , 3264.56(21) keV , 2.33(19) μs , , , 14− , , , - , ¹⁸¹W , style="text-align:right" , 74 , style="text-align:right" , 107 , 180.948197(5) , 121.2(2) d , EC , ¹⁸¹Ta , 9/2+ , , , - , ¹⁸²W , style="text-align:right" , 74 , style="text-align:right" , 108 , 181.9482042(9) , colspan=3 align=center,

Observationally Stable Stable nuclides are nuclides that are not radioactive and so (unlike radionuclides) do not spontaneously undergo radioactive decay. When such nuclides are referred to in relation to specific elements, they are usually termed stable isotopes. Th ...

Believed to undergo α decay to ¹⁷⁸Hf with a half-life over 7.7×10²¹ y , 0+ , 0.2650(16) , , - , ¹⁸³W , style="text-align:right" , 74 , style="text-align:right" , 109 , 182.9502230(9) , colspan=3 align=center, Observationally StableBelieved to undergo α decay to ¹⁷⁹Hf with a half-life over 4.1×10²¹ y , 1/2− , 0.1431(4) , , - , style="text-indent:1em" , ^183mW , colspan="3" style="text-indent:2em" , 309.493(3) keV , 5.2(3) s , IT , ¹⁸³W , 11/2+ , , , - , ¹⁸⁴W , style="text-align:right" , 74 , style="text-align:right" , 110 , 183.9509312(9) , colspan=3 align=center, Observationally StableBelieved to undergo α decay to ¹⁸⁰Hf with a half-life over 8.9×10²¹ y , 0+ , 0.3064(2) , , - , ¹⁸⁵W , style="text-align:right" , 74 , style="text-align:right" , 111 , 184.9534193(10) , 75.1(3) d , β⁻ , ¹⁸⁵Re , 3/2− , , , - , style="text-indent:1em" , ^185mW , colspan="3" style="text-indent:2em" , 197.43(5) keV , 1.597(4) min , IT , ¹⁸⁵W , 11/2+ , , , - , ¹⁸⁶W , style="text-align:right" , 74 , style="text-align:right" , 112 , 185.9543641(19) , colspan=3 align=center, Observationally StableBelieved to undergo α decay to ¹⁸²Hf or β⁻β⁻ decay to ''¹⁸⁶Os'' with a half-life over 8.2×10²¹ y , 0+ , 0.2843(19) , , - , style="text-indent:1em" , ^186m1W , colspan="3" style="text-indent:2em" , 1517.2(6) keV , 18(1) μs , , , (7−) , , , - , style="text-indent:1em" , ^186m2W , colspan="3" style="text-indent:2em" , 3542.8(21) keV , >3 ms , , , (16+) , , , - , ¹⁸⁷W , style="text-align:right" , 74 , style="text-align:right" , 113 , 186.9571605(19) , 23.72(6) h , β⁻ , ''¹⁸⁷Re'' , 3/2− , , , - , ¹⁸⁸W , style="text-align:right" , 74 , style="text-align:right" , 114 , 187.958489(4) , 69.78(5) d , β⁻ , ¹⁸⁸Re , 0+ , , , - , ¹⁸⁹W , style="text-align:right" , 74 , style="text-align:right" , 115 , 188.96191(21) , 11.6(3) min , β⁻ , ¹⁸⁹Re , (3/2−) , , , - , ¹⁹⁰W , style="text-align:right" , 74 , style="text-align:right" , 116 , 189.96318(18) , 30.0(15) min , β⁻ , ¹⁹⁰Re , 0+ , , , - , style="text-indent:1em" , ^190mW , colspan="3" style="text-indent:2em" , 2381(5) keV , <3.1 ms , , , (10−) , , , - , ¹⁹¹W , style="text-align:right" , 74 , style="text-align:right" , 117 , 190.96660(21)# , 20# s
300 ns, , , 3/2−# , , , - , ¹⁹²W , style="text-align:right" , 74 , style="text-align:right" , 118 , 191.96817(64)# , 10# s
300 ns, , , 0+ , ,

References

* Isotope masses from: ** * Isotopic compositions and standard atomic masses from: ** ** * Half-life, spin, and isomer data selected from the following sources. ** ** ** {{Navbox element isotopes Tungsten

Tungsten Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolat ...