Isotopes of radon

There are 39 known isotopes of radon (₈₆Rn), from ¹⁹³Rn to ²³¹Rn; all are radioactive. The most stable isotope is ²²²Rn with a half-life of 3.8215 days, which decays into .

Six isotopes of radon, ^217-222Rn, occur in trace quantities in nature as decay products of, respectively, ²¹⁷At, ²¹⁸At, ²²³Ra, ²²⁴Ra, ²²⁵Ra, and ²²⁶Ra. ²¹⁷Rn and ²²¹Rn are produced in rare branches in the decay chain of trace quantities of ²³⁷Np; ²²²Rn (and also ²¹⁸Rn in a rare branch) is an intermediate step in the decay chain of ²³⁸U; ²¹⁹Rn is an intermediate step in the decay chain of ²³⁵U; and ²²⁰Rn occurs in the decay chain of ²³²Th.

List of isotopes

|-id=Radon-193 | ¹⁹³Rn | | style="text-align:right" | 86 | style="text-align:right" | 107 | 193.009708(27) | 1.15(27) ms | α | ¹⁸⁹Po | (3/2−) | |-id=Radon-194 | ¹⁹⁴Rn | | style="text-align:right" | 86 | style="text-align:right" | 108 | 194.006146(18) | 780(160) μs | α | ¹⁹⁰Po | 0+ | |-id=Radon-195 | ¹⁹⁵Rn | | style="text-align:right" | 86 | style="text-align:right" | 109 | 195.005422(55) | 7(3)&nbsp;ms | α | ¹⁹¹Po | 3/2− | |-id=Radon-195m | style="text-indent:1em" | ^195mRn | | colspan="3" style="text-indent:2em" | 80(50) keV | 6(3)&nbsp;ms | α | ¹⁹¹Po | 13/2+ | |-id=Radon-196 | ¹⁹⁶Rn | | style="text-align:right" | 86 | style="text-align:right" | 110 | 196.002120(15) | 4.7(11)&nbsp;ms | α | ¹⁹²Po | 0+ | |-id=Radon-197 | ¹⁹⁷Rn | | style="text-align:right" | 86 | style="text-align:right" | 111 | 197.001621(17) | 54(6)&nbsp;ms | α | ¹⁹³Po | 3/2− | |-id=Radon-197m | style="text-indent:1em" | ^197mRn | | colspan="3" style="text-indent:2em" | 199(11)&nbsp;keV | 25.6(25)&nbsp;ms | α | ¹⁹³Po | 13/2+ | |-id=Radon-198 | ¹⁹⁸Rn | | style="text-align:right" | 86 | style="text-align:right" | 112 | 197.998679(14) | 64.4(16)&nbsp;ms | α | ¹⁹⁴Po | 0+ | |-id=Radon-199 | ¹⁹⁹Rn | | style="text-align:right" | 86 | style="text-align:right" | 113 | 198.9983254(78) | 590(30)&nbsp;ms | α | ¹⁹⁵Po | 3/2− | |-id=Radon-199m | style="text-indent:1em" | ^199mRn | | colspan="3" style="text-indent:2em" | 220(11)&nbsp;keV | 310(20)&nbsp;ms | α | ¹⁹⁵Po | 13/2+ | |-id=Radon-200 | ²⁰⁰Rn | | style="text-align:right" | 86 | style="text-align:right" | 114 | 199.9957053(62) | 1.09(16)&nbsp;s | α | ¹⁹⁶Po | 0+ | |-id=Radon-200m | style="text-indent:1em" | ^200mRn | | colspan="3" style="text-indent:2em" | 2320(20)#&nbsp;keV | 28(9)&nbsp;μs | IT | ²⁰⁰Rn | | |-id=Radon-201 | ²⁰¹Rn | | style="text-align:right" | 86 | style="text-align:right" | 115 | 200.995591(11) | 7.0(4)&nbsp;s | α | ¹⁹⁷Po | 3/2− | |-id=Radon-201m | style="text-indent:1em" | ^201mRn | | colspan="3" style="text-indent:2em" | 245(12)&nbsp;keV | 3.8(1)&nbsp;s | α | ¹⁹⁷Po | 13/2+ | |-id=Radon-202 | rowspan=2|²⁰²Rn | rowspan=2| | rowspan=2 style="text-align:right" | 86 | rowspan=2 style="text-align:right" | 116 | rowspan=2|201.993264(19) | rowspan=2|9.7(1)&nbsp;s | α (78%) | ¹⁹⁸Po | rowspan=2|0+ | rowspan=2| |- | β⁺ (22%) | ²⁰²At |-id=Radon-202m | style="text-indent:1em" | ^202mRn | | colspan="3" style="text-indent:2em" | 2310(50)#&nbsp;keV | 2.22(7)&nbsp;μs | IT | ²⁰²Rn | 11−# | |-id=Radon-203 | rowspan=2|²⁰³Rn | rowspan=2| | rowspan=2 style="text-align:right" | 86 | rowspan=2 style="text-align:right" | 117 | rowspan=2|202.9933612(62) | rowspan=2|44.2(16)&nbsp;s | α (66%) | ¹⁹⁹Po | rowspan=2|3/2− | rowspan=2| |- | β⁺ (34%) | ²⁰³At |-id=Radon-203m | rowspan=2 style="text-indent:1em" | ^203mRn | rowspan=2| | rowspan=2 colspan="3" style="text-indent:2em" | 362(4)&nbsp;keV | rowspan=2|26.9(5)&nbsp;s | α (75%) | ¹⁹⁹Po | rowspan=2|13/2+ | rowspan=2| |- | β⁺ (25%) | ²⁰³At |-id=Radon-204 | rowspan=2|²⁰⁴Rn | rowspan=2| | rowspan=2 style="text-align:right" | 86 | rowspan=2 style="text-align:right" | 118 | rowspan=2|203.9914437(80) | rowspan=2|1.242(23)&nbsp;min | α (72.4%) | ²⁰⁰Po | rowspan=2|0+ | rowspan=2| |- | β⁺ (27.6%) | ²⁰⁴At |-id=Radon-205 | rowspan=2|²⁰⁵Rn | rowspan=2| | rowspan=2 style="text-align:right" | 86 | rowspan=2 style="text-align:right" | 119 | rowspan=2|204.9917232(55) | rowspan=2|170(4)&nbsp;s | β⁺ (75.4%) | ²⁰⁵At | rowspan=2|5/2− | rowspan=2| |- | α (24.6%) | ²⁰¹Po |-id=Radon-205m | style="text-indent:1em" | ^205mRn | | colspan="3" style="text-indent:2em" | 657.1(5)&nbsp;keV | >10&nbsp;s | IT | ²⁰⁵Rn | 13/2+# | |-id=Radon-206 | rowspan=2|²⁰⁶Rn | rowspan=2| | rowspan=2 style="text-align:right" | 86 | rowspan=2 style="text-align:right" | 120 | rowspan=2|205.9901954(92) | rowspan=2|5.67(17)&nbsp;min | α (62%) | ²⁰²Po | rowspan=2|0+ | rowspan=2| |- | β⁺ (38%) | ²⁰⁶At |-id=Radon-207 | rowspan=2|²⁰⁷Rn | rowspan=2| | rowspan=2 style="text-align:right" | 86 | rowspan=2 style="text-align:right" | 121 | rowspan=2|206.9907302(51) | rowspan=2|9.25(17)&nbsp;min | β⁺ (79%) | ²⁰⁷At | rowspan=2|5/2− | rowspan=2| |- | α (21%) | ²⁰³Po |-id=Radon-207m | style="text-indent:1em" | ^207mRn | | colspan="3" style="text-indent:2em" | 899.1(10)&nbsp;keV | 184.5(9)&nbsp;μs | IT | ²⁰⁷Rn | 13/2+ | |-id=Radon-208 | rowspan=2|²⁰⁸Rn | rowspan=2| | rowspan=2 style="text-align:right" | 86 | rowspan=2 style="text-align:right" | 122 | rowspan=2|207.989635(11) | rowspan=2|24.35(14)&nbsp;min | α (62%) | ²⁰⁴Po | rowspan=2|0+ | rowspan=2| |- | β⁺ (38%) | ²⁰⁸At |-id=Radon-208m | style="text-indent:1em" | ^208mRn | | colspan="3" style="text-indent:2em" | 1828.3(4)&nbsp;keV | 487(12)&nbsp;ns | IT | ²⁰⁸Rn | 8+ | |-id=Radon-209 | rowspan=2|²⁰⁹Rn | rowspan=2| | rowspan=2 style="text-align:right" | 86 | rowspan=2 style="text-align:right" | 123 | rowspan=2|208.990401(11) | rowspan=2|28.8(10)&nbsp;min | β⁺ (83%) | ²⁰⁹At | rowspan=2|5/2− | rowspan=2| |- | α (17%) | ²⁰⁵Po |-id=Radon-209m1 | style="text-indent:1em" | ^209m1Rn | | colspan="3" style="text-indent:2em" | 1174.01(13)&nbsp;keV | 13.4(13)&nbsp;μs | IT | ²⁰⁹Rn | 13/2+ | |-id=Radon-209m2 | style="text-indent:1em" | ^209m2Rn | | colspan="3" style="text-indent:2em" | 3636.81(23)&nbsp;keV | 3.0(3)&nbsp;μs | IT | ²⁰⁹Rn | 35/2+ | |-id=Radon-210 | rowspan=2|²¹⁰Rn | rowspan=2| | rowspan=2 style="text-align:right" | 86 | rowspan=2 style="text-align:right" | 124 | rowspan=2|209.9896889(49) | rowspan=2|2.4(1)&nbsp;h | α (96%) | ²⁰⁶Po | rowspan=2|0+ | rowspan=2| |- | β⁺ (4%) | ²¹⁰At |-id=Radon-210m1 | style="text-indent:1em" | ^210m1Rn | | colspan="3" style="text-indent:2em" | 1710(30)&nbsp;keV | 644(40)&nbsp;ns | IT | ²¹⁰Rn | 8+ | |-id=Radon-210m2 | style="text-indent:1em" | ^210m2Rn | | colspan="3" style="text-indent:2em" | 3857(30)&nbsp;keV | 1.06(5)&nbsp;μs | IT | ²¹⁰Rn | 17− | |-id=Radon-210m3 | style="text-indent:1em" | ^210m3Rn | | colspan="3" style="text-indent:2em" | 6514(30)&nbsp;keV | 1.04(7)&nbsp;μs | IT | ²¹⁰Rn | 23+ | |-id=Radon-211 | rowspan=2|²¹¹Rn | rowspan=2| | rowspan=2 style="text-align:right" | 86 | rowspan=2 style="text-align:right" | 125 | rowspan=2|210.9906008(73) | rowspan=2|14.6(2)&nbsp;h | β⁺ (72.6%) | ²¹¹At | rowspan=2|1/2− | rowspan=2| |- | α (27.4%) | ²⁰⁷Po |-id=Radon-211m1 | style="text-indent:1em" | ^211m1Rn | | colspan="3" style="text-indent:2em" | 1603(14)#&nbsp;keV | 596(28)&nbsp;ns | IT | ²¹¹Rn | 17/2− | |-id=Radon-211m2 | style="text-indent:1em" | ^211m2Rn | | colspan="3" style="text-indent:2em" | 8905(20)#&nbsp;keV | 201(4)&nbsp;ns | IT | ²¹¹Rn | 63/2− | |-id=Radon-212 |²¹²Rn | |style="text-align:right" | 86 |style="text-align:right" | 126 |211.9907039(33) |23.9(12)&nbsp;min | α | ²⁰⁸Po |0+ | |-id=Radon-212m1 | style="text-indent:1em" | ^212m1Rn | | colspan="3" style="text-indent:2em" | 1639.68(15)&nbsp;keV | 118(14)&nbsp;ns | IT | ²¹²Rn | 6+ | |-id=Radon-212m2 | style="text-indent:1em" | ^212m2Rn | | colspan="3" style="text-indent:2em" | 1694.1(3)&nbsp;keV | 910(30)&nbsp;ns | IT | ²¹²Rn | 8+ | |-id=Radon-212m3 | style="text-indent:1em" | ^212m3Rn | | colspan="3" style="text-indent:2em" | 6174.2(3)&nbsp;keV | 102(4)&nbsp;ns | IT | ²¹²Rn | 22+ | |-id=Radon-212m4 | style="text-indent:1em" | ^212m4Rn | | colspan="3" style="text-indent:2em" | 8579.2(4)&nbsp;keV | 154(14)&nbsp;ns | IT | ²¹²Rn | 30+ | |-id=Radon-213 | ²¹³Rn | | style="text-align:right" | 86 | style="text-align:right" | 127 | 212.9938851(36) | 19.5(1)&nbsp;ms | α | ²⁰⁹Po | 9/2+# | |-id=Radon-213m1 | style="text-indent:1em" | ^213m1Rn | | colspan="3" style="text-indent:2em" | 1682(10)&nbsp;keV | 1.00(21)&nbsp;μs | IT | ²¹³Rn | (25/2+) | |-id=Radon-213m2 | style="text-indent:1em" | ^213m2Rn | | colspan="3" style="text-indent:2em" | 2205(10)&nbsp;keV | 1.36(7)&nbsp;μs | IT | ²¹³Rn | (31/2−) | |-id=Radon-213m3 | style="text-indent:1em" | ^213m3Rn | | colspan="3" style="text-indent:2em" | 5965(14)&nbsp;keV | 164(11)&nbsp;ns | IT | ²¹³Rn | (55/2+) | |-id=Radon-214 |²¹⁴Rn | | style="text-align:right" | 86 |style="text-align:right" | 128 |213.9953627(99) |259(3)&nbsp;ns | α | ²¹⁰Po |0+ | |-id=Radon-214m | style="text-indent:1em" | ^214mRn | | colspan="3" style="text-indent:2em" | 4595.4(18)&nbsp;keV | 245(30)&nbsp;ns |IT |²¹⁴Rn | (22+) | |-id=Radon-215 | ²¹⁵Rn | | style="text-align:right" | 86 | style="text-align:right" | 129 | 214.9987450(65) | 2.30(10)&nbsp;μs | α | ²¹¹Po | 9/2+ | |-id=Radon-216 | ²¹⁶Rn | | style="text-align:right" | 86 | style="text-align:right" | 130 | 216.0002719(62) | 29(4)&nbsp;μs | α | ²¹²Po | 0+ | |-id=Radon-217 | ²¹⁷Rn | | style="text-align:right" | 86 | style="text-align:right" | 131 | 217.0039276(45) | 593(38)&nbsp;μs | α | ²¹³Po | 9/2+ | Trace |-id=Radon-218 | ²¹⁸Rn | | style="text-align:right" | 86 | style="text-align:right" | 132 | 218.0056011(25) | 33.75(15)&nbsp;ms | α | ²¹⁴Po | 0+ | Trace |-id=Radon-219 | ²¹⁹Rn | Actinon<br/>Actinium emanation | style="text-align:right" | 86 | style="text-align:right" | 133 | 219.0094787(23) | 3.96(1)&nbsp;s | α | ²¹⁵Po | 5/2+ | Trace |-id=Radon-220 |²²⁰Rn |Thoron<br/>Thorium emanation | style="text-align:right" | 86 | style="text-align:right" | 134 | 220.0113924(19) |55.6(1)&nbsp;s | α | ²¹⁶Po |0+ |Trace |-id=Radon-221 | rowspan=2|²²¹Rn | rowspan=2| | rowspan=2 style="text-align:right" | 86 | rowspan=2 style="text-align:right" | 135 | rowspan=2|221.0155356(61) | rowspan=2|25.7(5)&nbsp;min | β^− (78%) | ²²¹Fr | rowspan=2|7/2+ | rowspan=2|Trace |- | α (22%) | ²¹⁷Po |- | ²²²Rn | Radon<br/>Radium emanation<br/>Emanation<br/>Emanon<br/>Niton | style="text-align:right" | 86 | style="text-align:right" | 136 | 222.0175760(21) | 3.8215(2)&nbsp;d | α | ²¹⁸Po | 0+ | Trace |-id=Radon-223 | rowspan=2|²²³Rn | rowspan=2| | rowspan=2 style="text-align:right" | 86 | rowspan=2 style="text-align:right" | 137 | rowspan=2|223.0218893(84) | rowspan=2|24.3(4)&nbsp;min | β^− | ²²³Fr | rowspan=2|7/2+ | rowspan=2| |- | α? | ²¹⁹Po |-id=Radon-224 | ²²⁴Rn | | style="text-align:right" | 86 | style="text-align:right" | 138 | 224.024096(11) | 107(3)&nbsp;min | β^− | ²²⁴Fr | 0+ | |-id=Radon-225 | ²²⁵Rn | | style="text-align:right" | 86 | style="text-align:right" | 139 | 225.028486(12) | 4.66(4)&nbsp;min | β^− | ²²⁵Fr | 7/2− | |-id=Radon-226 | ²²⁶Rn | | style="text-align:right" | 86 | style="text-align:right" | 140 | 226.030861(11) | 7.4(1)&nbsp;min | β^− | ²²⁶Fr | 0+ | |-id=Radon-227 | ²²⁷Rn | | style="text-align:right" | 86 | style="text-align:right" | 141 | 227.035304(15) | 20.2(4)&nbsp;s | β^− | ²²⁷Fr | (3/2+) | |-id=Radon-228 | ²²⁸Rn | | style="text-align:right" | 86 | style="text-align:right" | 142 | 228.037835(19) | 65(2)&nbsp;s | β^− | ²²⁸Fr | 0+ | |-id=Radon-229 | ²²⁹Rn | | style="text-align:right" | 86 | style="text-align:right" | 143 | 229.042257(14) | 11.9(13)&nbsp;s | β^− | ²²⁹Fr | (5/2+) | |-id=Radon-230 | ²³⁰Rn | | style="text-align:right" | 86 | style="text-align:right" | 144 | 230.04527(22)# | 24#&nbsp;s<br />[>300&nbsp;ns] | | | 0+ | |-id=Radon-231 | ²³¹Rn | | style="text-align:right" | 86 | style="text-align:right" | 145 | 231.04997(32)# | 2#&nbsp;s<br />[>300&nbsp;ns] | | | 1/2+# |

References

• Isotope masses from:
• Half-life, spin, and isomer data selected from the following sources.