Isotopes of oxygen - wikipedia Isotopes of oxygen Main isotopes of oxygen Isotope Decay abundance half - life ( t ) mode product O 99.76 % stable O 0.04 % stable O 0.20 % stable Standard atomic weight ( A ) ( 7001159990300000000 ♠ 15.999 03, 7001159997700000000 ♠ 15.999 77 ) Conventional : 15.999 view talk There are three known stable isotopes of oxygen ( O ) : O, O, and O. Radioactive isotopes with mass numbers from O to O have also been characterized, all short - lived, with the longest - lived being O with a half - life of 122.24 seconds, while the shortest - lived isotope is O with a half - life of 580 ( 30 ) × 10 second. Contents 1 Stable isotopes 2 Radioisotopes 2.1 Oxygen - 13 2.2 Oxygen - 15 3 List of isotopes 3.1 Notes 4 See also 5 Notes and references 6 References Stable isotopes Late in a massive star 's life, O concentrates in the O - shell, O in the H - shell and O in the He - shell Naturally occurring oxygen is composed of three stable isotopes, O, O, and O, with O being the most abundant ( 99.762 % natural abundance ). Depending on the terrestrial source, the standard atomic weight varies within the range of ( 15.99903, 15.99977 ) ( the conventional value is 15.999 ). Known oxygen isotopes range in mass number from 12 to 24. The relative and absolute abundance of O is high because it is a principal product of stellar evolution and because it is a primary isotope, meaning it can be made by stars that were initially made exclusively of hydrogen. Most O is synthesized at the end of the helium fusion process in stars ; the triple - alpha reaction creates C, which captures an additional He to make O. The neon burning process creates additional O. Both O and O are secondary isotopes, meaning that their nucleosynthesis requires seed nuclei. O is primarily made by the burning of hydrogen into helium during the CNO cycle, making it a common isotope in the hydrogen burning zones of stars. Most O is produced when N ( made abundant from CNO burning ) captures a He nucleus, making O common in the helium - rich zones of stars. Approximately a billion degrees Celsius is required for two oxygen nuclei to undergo nuclear fusion to form the heavier nucleus of sulfur. Measurements of the ratio of oxygen - 18 to oxygen - 16 are often used to interpret changes in paleoclimate. The isotopic composition of oxygen atoms in the Earth 's atmosphere is 99.759 % O, 0.037 % O and 0.204 % O. Because water molecules containing the lighter isotope are slightly more likely to evaporate and fall as precipitation, fresh water and polar ice on earth contains slightly less ( 0.1981 % ) of the heavy isotope O than air ( 0.204 % ) or seawater ( 0.1995 % ). This disparity allows analysis of temperature patterns via historic ice cores. An atomic mass of 16 was assigned to oxygen prior to the definition of the unified atomic mass unit based upon C. Since physicists referred to O only, while chemists meant the naturally - abundant mixture of isotopes, this led to slightly different mass scales between the two disciplines. Radioisotopes Fourteen radioisotopes have been characterized, with the most stable being O with a half - life of 122.24 s and O with a half - life of 70.606 s. All of the remaining radioactive isotopes have half - lives that are less than 27 s and the majority of these have half - lives that are less than 83 milliseconds ( ms ). For example, O has a half - life of 61 ms. The most common decay mode for isotopes lighter than the stable isotopes is β decay ( to nitrogen ) and the most common mode after is β decay ( to fluorine ). Oxygen - 13 Oxygen - 13 is an unstable isotope of oxygen. It consists of 8 protons and electrons, and 5 neutrons. It has a spin of 3 / 2 -, and a half - life of 8.58 ms. Its atomic mass is 13.0248 Da. It decays to nitrogen - 13 by electron capture, and has a decay energy of 17.765 MeV. Its parent nuclide is fluorine - 14. Oxygen - 15 Oxygen - 15 is an isotope of oxygen, frequently used in positron emission tomography, or PET imaging. It has 8 protons, 7 neutrons, and 8 electrons. The total atomic mass is 15.0030654 amu. It has a half - life of 122.24 seconds. Oxygen - 15 is synthesized through deuteron bombardment of nitrogen - 14 using a cyclotron. List of isotopes nuclide symbol Z ( p ) N ( n ) isotopic mass ( u ) half - life decay mode ( s ) daughter isotope ( s ) nuclear spin representative isotopic composition ( mole fraction ) range of natural variation ( mole fraction ) O 8 12.034405 ( 20 ) 580 ( 30 ) × 10 s ( 0.40 ( 25 ) MeV ) 2p ( 60.0 % ) 0 + p ( 40.0 % ) O 8 5 13.024812 ( 10 ) 8.58 ( 5 ) ms β ( 89.1 % ) ( 3 / 2 − ) β, p ( 10.9 % ) O 8 6 14.00859625 ( 12 ) 70.598 ( 18 ) s β 0 + O 8 7 15.0030656 ( 5 ) 122.24 ( 16 ) s β 1 / 2 − O 8 8 15.99491461956 ( 16 ) Stable 0 + 0.99757 ( 16 ) 0.99738 -- 0.99776 O 8 9 16.99913170 ( 12 ) Stable 5 / 2 + 3.8 ( 1 ) × 10 3.7 × 10 -- 4.0 × 10 O 8 10 17.9991610 ( 7 ) Stable 0 + 2.05 ( 14 ) × 10 1.88 × 10 -- 2.22 × 10 O 8 11 19.003580 ( 3 ) 26.464 ( 9 ) s β 5 / 2 + O 8 12 20.0040767 ( 12 ) 13.51 ( 5 ) s β 0 + O 8 13 21.008656 ( 13 ) 3.42 ( 10 ) s β ( 1 / 2, 3 / 2, 5 / 2 ) + O 8 14 22.00997 ( 6 ) 2.25 ( 15 ) s β ( 78.0 % ) 0 + β, n ( 22.0 % ) O 8 15 23.01569 ( 13 ) 82 ( 37 ) ms β, n ( 57.99 % ) 1 / 2 + # β ( 42.0 % ) O 8 16 24.02047 ( 25 ) 65 ( 5 ) ms β, n ( 57.99 % ) 0 + β ( 42.01 % ) Jump up ^ Bold for stable isotopes ^ Jump up to : The ratio between O and O is used to deduce ancient temperatures Jump up ^ Can be used in NMR studies of metabolic pathways Jump up ^ Can be used in studying certain metabolic pathways Oxygen isotopes with 25 -- 28 nucleons exist for less than 1 microsecond, since they are beyond the neutron drip line. Notes The precision of the isotope abundances and atomic mass is limited through variations. The given ranges should be applicable to any normal terrestrial material. Values marked # are not purely derived from experimental data, but at least partly from systematic trends. Spins with weak assignment arguments are enclosed in parentheses. Uncertainties are given in concise form in parentheses after the corresponding last digits. Uncertainty values denote one standard deviation, except isotopic composition and standard atomic mass from IUPAC, which use expanded uncertainties. Nuclide masses are given by IUPAP Commission on Symbols, Units, Nomenclature, Atomic Masses and Fundamental Constants ( SUNAMCO ). Isotope abundances are given by IUPAC Commission on Isotopic Abundances and Atomic Weights ( CIAAW ). See also Dole effect Notes and references Jump up ^ Meija, J. ; et al. ( 2016 ). `` Atomic weights of the elements 2013 ( IUPAC Technical Report ) ''. Pure Appl. Chem. 88 ( 3 ) : 265 -- 91. doi : 10.1515 / pac - 2015 - 0305. ^ Jump up to : B.S. Meyer ( September 19 -- 21, 2005 ). `` Nucleosynthesis and galactic chemical evolution of the isotopes of oxygen '' ( PDF ). Proceedings of the NASA Cosmochemistry Program and the Lunar and Planetary Institute. Workgroup on Oxygen in the Earliest Solar System. Gatlinburg, Tennessee. 9022. Jump up ^ Emsley 2001, p. 297. Jump up ^ Cook 1968, p. 500. Jump up ^ Dansgaard, W ( 1964 ). `` Stable isotopes in precipitation '' ( PDF ). Tellus. 16 : 436 -- 468. doi : 10.1111 / j. 2153 - 3490.1964. tb00181. x. Jump up ^ Parks & Mellor 1939, Chapter VI, Section 7. ^ Jump up to : K.L. Barbalace. `` Periodic Table of Elements : O - Oxygen ''. EnvironmentalChemistry.com. Retrieved 2007 - 12 - 17. Jump up ^ Ekström, L.P. ; Firestone, R.B. ( 28 February 1999 ). `` Oxygen - 24 ''. WWW Table of Radioactive Isotopes. LUNDS Universitet, LBNL Isotopes Project. Retrieved 2009 - 06 - 08. Jump up ^ `` NUDAT ''. Retrieved 2009 - 07 - 06. Jump up ^ `` NUDAT ''. Retrieved 2009 - 07 - 06. Jump up ^ `` NUDAT ''. Retrieved 2009 - 07 - 06. Jump up ^ `` Periodic Table of Elements : O - Oxygen ''. EnvironmentalChemistry.com. 1995 - 10 - 22. Retrieved 2014 - 12 - 02. Jump up ^ `` Periodic Table of Elements : F - Fluorine ''. EnvironmentalChemistry.com. 1995 - 10 - 22. Retrieved 2014 - 12 - 02. Jump up ^ `` oxygen 15 - definition of oxygen 15 by Medical dictionary ''. Medical-dictionary.thefreedictionary.com. Retrieved 2014 - 12 - 02. Jump up ^ `` Production of PET Radionuclides ''. Austin Hospital, Austin Health. Retrieved 6 December 2012. Jump up ^ `` Universal Nuclide Chart ''. Nucleonica. Retrieved 2014 - 12 - 02. ( Registration required ( help ) ). Jump up ^ `` Nuclear Physicists Examine Oxygen 's Limits ''. Science Daily. 2007 - 09 - 18. Retrieved 2010 - 09 - 16. References For the table Isotope masses from the area : G. Audi ; A.H. Wapstra ; C. Thibault ; J. Blachot ; O. Bersillon ( 2003 ). `` The NUBASE evaluation of nuclear and decay properties '' ( PDF ). Nuclear Physics A. 729 : 3 -- 128. Bibcode : 2003NuPhA. 729... 3A. doi : 10.1016 / j. nuclphysa. 2003.11. 001. Archived from the original ( PDF ) on 2008 - 09 - 23. Isotopic compositions and standard atomic masses from : 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 ) '' ( PDF ). Pure and Applied Chemistry. 75 ( 6 ) : 683 -- 800. doi : 10.1351 / pac200375060683. M.E. Wieser ( 2006 ). `` Atomic weights of the elements 2005 ( IUPAC Technical Report ) ''. Pure and Applied Chemistry. 78 ( 11 ) : 2051 -- 2066. doi : 10.1351 / pac200678112051. Lay summary. Half - life, spin, and isomer data selected from the following sources. See editing notes on this article 's talk page. G. Audi ; A.H. Wapstra ; C. Thibault ; J. Blachot ; O. Bersillon ( 2003 ). `` The NUBASE evaluation of nuclear and decay properties '' ( PDF ). Nuclear Physics A. 729 : 3 -- 128. Bibcode : 2003NuPhA. 729... 3A. doi : 10.1016 / j. nuclphysa. 2003.11. 001. Archived from the original ( PDF ) on 2008 - 09 - 23. National Nuclear Data Center. `` NuDat 2.1 database ''. Brookhaven National Laboratory. Retrieved September 2005. Check date values in : access - date = ( help ) N.E. Holden ( 2004 ). `` Table of the Isotopes ''. In D.R. Lide. CRC Handbook of Chemistry and Physics ( 85th ed. ). CRC Press. Section 11. ISBN 978 - 0 - 8493 - 0485 - 9. For the prose Cook, Gerhard A. ; Lauer, Carol M. ( 1968 ). `` Oxygen ''. In Clifford A. Hampel. The Encyclopedia of the Chemical Elements. New York : Reinhold Book Corporation. pp. 499 -- 512. LCCN 68 - 29938. Emsley, John ( 2001 ). `` Oxygen ''. Nature 's Building Blocks : An A -- Z Guide to the Elements. Oxford, England, UK : Oxford University Press. pp. 297 -- 304. ISBN 0 - 19 - 850340 - 7. Parks, G.D. ; Mellor, J.W. ( 1939 ). Mellor 's Modern Inorganic Chemistry ( 6th ed. ). London : Longmans, Green and Co. Isotopes of nitrogen Isotopes of oxygen Isotopes of fluorine Table of nuclides Isotopes of the chemical elements He Li Be 5 6 7 8 O 9 10 Ne 11 Na 12 Mg 13 Al 14 Si 15 16 17 Cl 18 Ar 19 20 Ca 21 Sc 22 Ti 23 V 24 Cr 25 Mn 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 31 Ga 32 Ge 33 As 34 Se 35 Br 36 Kr 37 Rb 38 Sr 39 Y 40 Zr 41 Nb 42 Mo 43 Tc 44 Ru 45 Rh 46 Pd 47 Ag 48 Cd 49 In 50 Sn 51 Sb 52 Te 53 54 Xe 55 Cs 56 Ba 57 La 72 Hf 73 Ta 74 75 Re 76 Os 77 Ir 78 Pt 79 Au 80 Hg 81 Tl 82 Pb 83 Bi 84 Po 85 At 86 Rn 87 Fr 88 Ra 89 Ac 104 Rf 105 Db 106 Sg 107 Bh 108 Hs 109 Mt 110 Ds 111 Rg 112 Cn 113 Nh 114 Fl 115 Mc 116 Lv 117 Ts 118 Og 58 Ce 59 Pr 60 Nd 61 Pm 62 Sm 63 Eu 64 Gd 65 Tb 66 Dy 67 Ho 68 Er 69 Tm 70 Yb 71 Lu 90 Th 91 Pa 92 U 93 Np 94 Pu 95 Am 96 Cm 97 Bk 98 Cf 99 Es 100 Fm 101 Md 102 No 103 Lr Table of nuclides Categories : Isotopes Tables of nuclides Metastable isotopes Isotopes by element Retrieved from `` https://en.wikipedia.org/w/index.php?title=Isotopes_of_oxygen&oldid=805844483 '' Categories : Oxygen Isotopes of oxygen Lists of isotopes by element Hidden categories : Pages with login required references or sources All articles with failed verification Articles with failed verification from April 2013 All articles with unsourced statements Articles with unsourced statements from April 2013 CS1 errors : dates Talk Contents About Wikipedia Català Чӑвашла Čeština Español Esperanto فارسی Français 한국어 Қазақша Magyar Nederlands 日本 語 Русский Suomi Svenska Türkçe Tiếng Việt 粵語 中文 Edit links This page was last edited on 18 October 2017, at 00 : 22. 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Question: how many isotopes of oxygen occur naturally on earth
Answer: three stable isotopes