Isotopes of krypton

There are 33 known isotopes of krypton (Kr) from 69 to 101. ^[1] Naturally occurring krypton is made of six stable isotopes, two of which may be slightly radioactive. Its spectral signature can be produced with some very sharp lines. ⁸¹Kr, the product of atmospheric reactions is produced with the other naturally occurring isotopes of krypton. It is radioactive with a half-life of 229,000 years. Krypton is highly volatile when it is near surface waters and ⁸¹Kr has been used for dating old (50,000 - 800,000 year) groundwater.^[2]

⁸⁵Kr is an inert radioactive noble gas with a half-life of 10.76 years. It is produced by fission of uranium and plutonium in nuclear bomb testing and nuclear reactors. It is released during the reprocessing of fuel rods from nuclear reactors. Concentrations at the North Pole are 30% higher than at the South Pole as most nuclear reactors are in the northern hemisphere.^[3] All other isotopes have half-lives under a day, except ⁷⁹Kr with a half-life of 35.04 10 hours.

Standard atomic mass: 83.798(2) u

1 Table
- 1.1 Notes
2 References
3 External links

Table

nuclide symbol	Z(p)	N(n)	isotopic mass (u)	half-life	decay mode(s)^[4]^{[n 1]}	daughter isotope(s)^{[n 2]}	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
nuclide symbol	excitation energy			half-life	decay mode(s)^[4]^{[n 1]}	daughter isotope(s)^{[n 2]}	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
⁶⁹Kr	36	33	68.96518(43)#	32(10) ms	β⁺	⁶⁹Br	5/2-#
⁷⁰Kr	36	34	69.95526(41)#	52(17) ms	β⁺	⁷⁰Br	0+
⁷¹Kr	36	35	70.94963(70)	100(3) ms	β⁺ (94.8%)	⁷¹Br	(5/2)-
⁷¹Kr	36	35	70.94963(70)	100(3) ms	β⁺, p (5.2%)	⁷⁰Se	(5/2)-
⁷²Kr	36	36	71.942092(9)	17.16(18) s	β⁺	⁷²Br	0+
⁷³Kr	36	37	72.939289(7)	28.6(6) s	β⁺ (99.32%)	⁷³Br	3/2-
⁷³Kr	36	37	72.939289(7)	28.6(6) s	β⁺, p (.68%)	⁷²Se	3/2-
^73mKr	433.66(12) keV			107(10) ns			(9/2+)
⁷⁴Kr	36	38	73.9330844(22)	11.50(11) min	β⁺	⁷⁴Br	0+
⁷⁵Kr	36	39	74.930946(9)	4.29(17) min	β⁺	⁷⁵Br	5/2+
⁷⁶Kr	36	40	75.925910(4)	14.8(1) h	β⁺	⁷⁶Br	0+
⁷⁷Kr	36	41	76.9246700(21)	74.4(6) min	β⁺	⁷⁷Br	5/2+
⁷⁸Kr	36	42	77.9203648(12)	Observationally Stable^{[n 3]}			0+	0.00355(3)
⁷⁹Kr	36	43	78.920082(4)	35.04(10) h	β⁺	⁷⁹Br	1/2-
^79mKr	129.77(5) keV			50(3) s			7/2+
⁸⁰Kr	36	44	79.9163790(16)	Stable			0+	0.02286(10)
⁸¹Kr^{[n 4]}	36	45	80.9165920(21)	2.29(11)×10⁵ a	EC	⁸¹Br	7/2+
^81mKr	190.62(4) keV			13.10(3) s	IT (99.975%)	⁸¹Kr	1/2-
^81mKr	190.62(4) keV			13.10(3) s	EC (.025%)	⁸¹Br	1/2-
⁸²Kr	36	46	81.9134836(19)	Stable			0+	0.11593(31)
⁸³Kr^{[n 5]}	36	47	82.914136(3)	Stable			9/2+	0.11500(19)
^83m1Kr	9.4053(8) keV			154.4(11) ns	7/2+
^83m2Kr	41.5569(10) keV			1.83(2) h	IT	⁸³Kr	1/2-
⁸⁴Kr^{[n 5]}	36	48	83.911507(3)	Stable			0+	0.56987(15)
^84mKr	3236.02(18) keV			1.89(4) µs			8+
⁸⁵Kr^{[n 5]}	36	49	84.9125273(21)	10.776(3) a	β^-	⁸⁵Rb	9/2+
^85m1Kr	304.871(20) keV			4.480(8) h	β^- (78.6%)	⁸⁵Rb	1/2-
^85m1Kr	304.871(20) keV			4.480(8) h	IT (21.4%)	⁸⁵Kr	1/2-
^85m2Kr	1991.8(13) keV			1.6(7) µs [1.2(+10-4) µs]			(17/2+)
⁸⁶Kr^{[n 5]}	36	50	85.91061073(11)	Observationally Stable^{[n 6]}			0+	0.17279(41)
⁸⁷Kr	36	51	86.91335486(29)	76.3(5) min	β^-	⁸⁷Rb	5/2+
⁸⁸Kr	36	52	87.914447(14)	2.84(3) h	β^-	⁸⁸Rb	0+
⁸⁹Kr	36	53	88.91763(6)	3.15(4) min	β^-	⁸⁹Rb	3/2(+#)
⁹⁰Kr	36	54	89.919517(20)	32.32(9) s	β^-	^90mRb	0+
⁹¹Kr	36	55	90.92345(6)	8.57(4) s	β^-	⁹¹Rb	5/2(+)
⁹²Kr	36	56	91.926156(13)	1.840(8) s	β^- (99.96%)	⁹²Rb	0+
⁹²Kr	36	56	91.926156(13)	1.840(8) s	β^-, n (.033%)	⁹¹Rb	0+
⁹³Kr	36	57	92.93127(11)	1.286(10) s	β^- (98.05%)	⁹³Rb	1/2+
⁹³Kr	36	57	92.93127(11)	1.286(10) s	β^-, n (1.95%)	⁹²Rb	1/2+
⁹⁴Kr	36	58	93.93436(32)#	210(4) ms	β^- (94.3%)	⁹⁴Rb	0+
⁹⁴Kr	36	58	93.93436(32)#	210(4) ms	β^-, n (5.7%)	⁹³Rb	0+
⁹⁵Kr	36	59	94.93984(43)#	114(3) ms	β^-	⁹⁵Rb	1/2(+)
⁹⁶Kr	36	60	95.94307(54)#	80(7) ms	β^-	⁹⁶Rb	0+
⁹⁷Kr	36	61	96.94856(54)#	63(4) ms	β^-	⁹⁷Rb	3/2+#
⁹⁷Kr	36	61	96.94856(54)#	63(4) ms	β^-, n	⁹⁶Rb	3/2+#
⁹⁸Kr	36	62	97.95191(64)#	46(8) ms			0+
⁹⁹Kr	36	63	98.95760(64)#	40(11) ms			(3/2+)#
¹⁰⁰Kr	36	64	99.96114(54)#	10# ms [>300 ns]			0+
¹⁰¹Kr ^{[n 7]}	36	65	unknown	>635 ns	β^- 2n , β^- n, β^-	(in order of decay mode) ⁹⁹Rb, ¹⁰⁰Rb, ¹⁰¹Rb	unknown	syn	syn

^ Abbreviations:
EC: Electron capture
IT: Isomeric transition
^ Bold for stable isotopes, bold italics for nearly-stable isotopes (half-life longer than the age of the universe)
^ Believed to decay by β⁺β⁺ to ⁷⁸Se with a half-life of more than >1.1×10²⁰ years
^ Used to date groundwater
^ ^a ^b ^c ^d Fission product
^ Believed to decay by β^-β^- to ⁸⁶Sr
^ New isotope.

Notes

The isotopic composition refers to that in air.
Geologically exceptional samples are known in which the isotopic composition lies outside the reported range. The uncertainty in the atomic mass may exceed the stated value for such specimens.
Commercially available materials may have been subjected to an undisclosed or inadvertent isotopic fractionation. Substantial deviations from the given mass and composition can occur.
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.

References

^ Brookhaven National Laboratory: Meet krypton's newest isotope, ¹⁰¹Kr, discover info about krypton's newest isotope, ¹⁰¹Kr, discovered in late 2011.
^ N. Thonnard, L. D. MeKay, T. C. Labotka (2001). "Development of Laser-Based Resonance Ionization Techniques for 81-Kr and 85-Kr Measurements in the Geosciences". University of Tennessee, Institute for Rare Isotope Measurements. pp. 4–7. http://www.osti.gov/bridge/servlets/purl/809813-0zMCV1/native/809813.pdf.
^ "Resources on Isotopes". U.S. Geological Survey. http://wwwrcamnl.wr.usgs.gov/isoig/period/kr_iig.html. Retrieved 2007-03-20.
^ http://www.nucleonica.net/unc.aspx

Isotope masses from:
- G. Audi, A. H. Wapstra, C. Thibault, J. Blachot and O. Bersillon (2003). "The NUBASE evaluation of nuclear and decay properties". Nuclear Physics A 729: 3–128. Bibcode 2003NuPhA.729....3A. doi:10.1016/j.nuclphysa.2003.11.001. http://www.nndc.bnl.gov/amdc/nubase/Nubase2003.pdf.
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 and P. D. P. Taylor (2003). "Atomic weights of the elements. Review 2000 (IUPAC Technical Report)". Pure and Applied Chemistry 75 (6): 683–800. doi:10.1351/pac200375060683. http://www.iupac.org/publications/pac/75/6/0683/pdf/.
- 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. http://iupac.org/publications/pac/78/11/2051/pdf/. 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 and O. Bersillon (2003). "The NUBASE evaluation of nuclear and decay properties". Nuclear Physics A 729: 3–128. Bibcode 2003NuPhA.729....3A. doi:10.1016/j.nuclphysa.2003.11.001. http://www.nndc.bnl.gov/amdc/nubase/Nubase2003.pdf.
- National Nuclear Data Center. "NuDat 2.1 database". Brookhaven National Laboratory. http://www.nndc.bnl.gov/nudat2/. Retrieved September 2005.
- 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 978-0849304859.

External links

Brookhaven National Laboratory: Krypton-101 information

Isotopes of bromine	Isotopes of krypton	Isotopes of rubidium
Index to isotope pages · Table of nuclides

Isotopes of krypton

Contents

Table

Notes

References

External links