Radon

Radon (Rn)

Colorless radioactive gaseous element, belongs to the noble gases. Of the twenty known isotopes, the most stable is Rn-222 with a half-life of 3.8 days. Formed by the radioactive decay of Radium-226. Radon itself decays into Polonium. Used in radiotherapy. As a noble gas, it is effectively inert, though radon fluoride has been synthesized. First isolated in 1908 by Ramsey and Gray.
Atomic Number86
Atomic Weight222
Mass Number193
Group18
Period6
Blockp
Protons86 p+
Neutrons107 n0
Electrons86 e-
Radon water apparatus P1120815.JPG Radon spectrum visible.png Animated Bohr Model of Rn (Radon) Enhanced Bohr Model of Rn (Radon) Bohr Model: Rn (Radon) Orbital Diagram of Rn (Radon)

Properties

Atomic Radius
Molar Volume
Covalent Radius
142 pm
Metallic Radius
Ionic Radius
Crystal Radius
Van der Waals Radius
220 pm
Density
0.009074 g/cm³
Energy
Proton Affinity
Electron Affinity
Ionization Energy
10.7485 eV/particle
Heat of Vaporization
18.1 kJ/mol
Heat of Fusion
Heat of Formation
Electrons
Electron Shells2, 8, 18, 32, 18, 8
Valence Electrons6
Electron Configuration[Xe] 4f14 5d10 6s2 6p6
Oxidation States2, 6
Electronegativity
Electrophilicity
Phases
PhaseGas
Gas PhaseMonoatomic
Boiling Point
211.45 K
Melting Point
202.15 K
Critical Pressure
6.28 MPa
Critical Temperature
377.15 K
Triple Point
Visual
Color
Colorless
Appearancecolorless gas, occasionally glows green or red in discharge tubes
Refractive Index
Thermodynamic Properties
Thermal Conductivity
0.0036 W/(m K)
Thermal Expansion
Molar Heat Capacity
20.786 J/(mol K)
Specific Heat Capacity
0.094 J/(g⋅K)
Heat Capacity Ratio (Adiabatic Index)5/3
Electrical Properties
Type
Electrical Conductivity
Electrical Resistivity
Superconducting Point
Magnetism
Type
Magnetic Susceptibility (Mass)
Magnetic Susceptibility (Molar)
Magnetic Susceptibility (Volume)
Magnetic Ordering
Curie Point
Neel Point
Structure
Crystal Structure (FCC)
Lattice Constant
Lattice Angles
Mechanical Properties
Hardness
Bulk Modulus
Shear Modulus
Young Modulus
Poisson Ratio
Speed of Sound
Classification
CategoryNoble gases, Noble gases
CAS GroupVIII
IUPAC GroupVIIIA
Glawe Number6
Mendeleev Number117
Pettifor Number6
Geochemical ClassU/Th decay series
Goldschmidt Classsynthetic
Other
Gas Basicity
Dipole Polarizability
35 ± 2 a₀
C6 Dispersion Coefficient
Allotropes
Neutron Cross Section
0.7
Neutron Mass Absorption
Quantum Numbers1S0
Space Group ()

Isotopes of Radon

Stable Isotopes0
Unstable Isotopes39
Radioactive Isotopes39

193Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
193.009707973 ± 0.000026958 Da
Mass Number193
G-Factor
Half Life
1.15 ± 0.27 ms
Spin3/2
Quadrupole Moment
Discovery Year2006
Parity-

193Rn Decay Modes
Decay ModeIntensity
α (α emission)100%

194Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
194.006145636 ± 0.000017884 Da
Mass Number194
G-Factor
0
Half Life
780 ± 160 us
Spin0
Quadrupole Moment
0
Discovery Year2006
Parity+

194Rn Decay Modes
Decay ModeIntensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)%

195Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
195.005421703 ± 0.000055487 Da
Mass Number195
G-Factor
Half Life
7 ± 3 ms
Spin3/2
Quadrupole Moment
Discovery Year2001
Parity-

195Rn Decay Modes
Decay ModeIntensity
α (α emission)100%

196Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
196.002120431 ± 0.000015087 Da
Mass Number196
G-Factor
0
Half Life
4.7 ± 1.1 ms
Spin0
Quadrupole Moment
0
Discovery Year1995
Parity+

196Rn Decay Modes
Decay ModeIntensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)%

197Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
197.001621446 ± 0.000017383 Da
Mass Number197
G-Factor
Half Life
54 ± 6 ms
Spin3/2
Quadrupole Moment
Discovery Year1995
Parity-

197Rn Decay Modes
Decay ModeIntensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)%

198Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
197.998679197 ± 0.000014406 Da
Mass Number198
G-Factor
0
Half Life
64.4 ± 1.6 ms
Spin0
Quadrupole Moment
0
Discovery Year1984
Parity+

198Rn Decay Modes
Decay ModeIntensity
α (α emission)93%
β+ (β+ decay; β+ = ϵ + e+)%

199Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
198.998325436 ± 0.000007833 Da
Mass Number199
G-Factor
Half Life
590 ± 30 ms
Spin3/2
Quadrupole Moment
Discovery Year1980
Parity-

199Rn Decay Modes
Decay ModeIntensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)%

200Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
199.995705335 ± 0.000006217 Da
Mass Number200
G-Factor
0
Half Life
1.09 ± 0.16 s
Spin0
Quadrupole Moment
0
Discovery Year1971
Parity+

200Rn Decay Modes
Decay ModeIntensity
α (α emission)92%
β+ (β+ decay; β+ = ϵ + e+)%

201Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
200.995590511 ± 0.000010865 Da
Mass Number201
G-Factor
Half Life
7 ± 0.4 s
Spin3/2
Quadrupole Moment
Discovery Year1967
Parity-

201Rn Decay Modes
Decay ModeIntensity
α (α emission)%
β+ (β+ decay; β+ = ϵ + e+)%

202Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
201.993263982 ± 0.000018808 Da
Mass Number202
G-Factor
0
Half Life
9.7 ± 0.1 s
Spin0
Quadrupole Moment
0
Discovery Year1967
Parity+

202Rn Decay Modes
Decay ModeIntensity
α (α emission)78%
β+ (β+ decay; β+ = ϵ + e+)%

203Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
202.993361155 ± 0.000006242 Da
Mass Number203
G-Factor
Half Life
44.2 ± 1.6 s
Spin3/2
Quadrupole Moment
Discovery Year1967
Parity-

203Rn Decay Modes
Decay ModeIntensity
α (α emission)66%
β+ (β+ decay; β+ = ϵ + e+)34%

204Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
203.991443729 ± 0.000007991 Da
Mass Number204
G-Factor
0
Half Life
1.242 ± 0.023 m
Spin0
Quadrupole Moment
0
Discovery Year1967
Parity+

204Rn Decay Modes
Decay ModeIntensity
α (α emission)72.4%
β+ (β+ decay; β+ = ϵ + e+)%

205Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
204.991723228 ± 0.000005453 Da
Mass Number205
G-Factor
0.3192 ± 0.00064
Half Life
170 ± 4 s
Spin5/2
Quadrupole Moment
0.062 ± 0.006
Discovery Year1967
Parity-

205Rn Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)75.4%
α (α emission)24.6%

206Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
205.990195409 ± 0.000009223 Da
Mass Number206
G-Factor
0
Half Life
5.67 ± 0.17 m
Spin0
Quadrupole Moment
0
Discovery Year1954
Parity+

206Rn Decay Modes
Decay ModeIntensity
α (α emission)62%
β+ (β+ decay; β+ = ϵ + e+)38%

207Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
206.990730224 ± 0.00000509 Da
Mass Number207
G-Factor
0.32496 ± 0.00064
Half Life
9.25 ± 0.17 m
Spin5/2
Quadrupole Moment
0.22 ± 0.02
Discovery Year1954
Parity-

207Rn Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)79%
α (α emission)21%

208Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
207.989634513 ± 0.00001091 Da
Mass Number208
G-Factor
0
Half Life
24.35 ± 0.14 m
Spin0
Quadrupole Moment
0
Discovery Year1955
Parity+

208Rn Decay Modes
Decay ModeIntensity
α (α emission)62%
β+ (β+ decay; β+ = ϵ + e+)38%

209Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
208.990401389 ± 0.000010692 Da
Mass Number209
G-Factor
Half Life
28.8 ± 1 m
Spin5/2
Quadrupole Moment
Discovery Year1952
Parity-

209Rn Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)83%
α (α emission)17%

210Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
209.989688862 ± 0.000004892 Da
Mass Number210
G-Factor
0
Half Life
2.4 ± 0.1 h
Spin0
Quadrupole Moment
0
Discovery Year1952
Parity+

210Rn Decay Modes
Decay ModeIntensity
α (α emission)96%
β+ (β+ decay; β+ = ϵ + e+)%

211Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
210.990600767 ± 0.000007314 Da
Mass Number211
G-Factor
1.1968 ± 0.0024
Half Life
14.6 ± 0.2 h
Spin1/2
Quadrupole Moment
0
Discovery Year1952
Parity-

211Rn Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)72.6%
α (α emission)27.4%

212Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
211.990703946 ± 0.000003338 Da
Mass Number212
G-Factor
0
Half Life
23.9 ± 1.2 m
Spin0
Quadrupole Moment
0
Discovery Year1950
Parity+

212Rn Decay Modes
Decay ModeIntensity
α (α emission)100%

213Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
212.993885147 ± 0.000003618 Da
Mass Number213
G-Factor
Half Life
19.5 ± 0.1 ms
Spin9/2
Quadrupole Moment
Discovery Year1967
Parity+

213Rn Decay Modes
Decay ModeIntensity
α (α emission)100%

214Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
213.99536265 ± 0.000009862 Da
Mass Number214
G-Factor
0
Half Life
259 ± 3 ns
Spin0
Quadrupole Moment
0
Discovery Year1970
Parity+

214Rn Decay Modes
Decay ModeIntensity
α (α emission)100%

215Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
214.998745037 ± 0.000006538 Da
Mass Number215
G-Factor
Half Life
2.3 ± 0.1 us
Spin9/2
Quadrupole Moment
Discovery Year1952
Parity+

215Rn Decay Modes
Decay ModeIntensity
α (α emission)100%

216Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
216.000271942 ± 0.000006192 Da
Mass Number216
G-Factor
0
Half Life
29 ± 4 us
Spin0
Quadrupole Moment
0
Discovery Year1949
Parity+

216Rn Decay Modes
Decay ModeIntensity
α (α emission)100%

217Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
217.003927632 ± 0.000004506 Da
Mass Number217
G-Factor
Half Life
593 ± 38 us
Spin9/2
Quadrupole Moment
Discovery Year1949
Parity+

217Rn Decay Modes
Decay ModeIntensity
α (α emission)100%

218Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
218.005601123 ± 0.000002486 Da
Mass Number218
G-Factor
0
Half Life
33.75 ± 0.15 ms
Spin0
Quadrupole Moment
0
Discovery Year1948
Parity+

218Rn Decay Modes
Decay ModeIntensity
α (α emission)100%

219Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
219.009478683 ± 0.000002254 Da
Mass Number219
G-Factor
-0.17596 ± 0.00048
Half Life
3.96 ± 0.01 s
Spin5/2
Quadrupole Moment
1.15 ± 0.12
Discovery Year1903
Parity+

219Rn Decay Modes
Decay ModeIntensity
α (α emission)100%

220Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
220.011392443 ± 0.000001947 Da
Mass Number220
G-Factor
0
Half Life
55.6 ± 0.1 s
Spin0
Quadrupole Moment
0
Discovery Year1900
Parity+

220Rn Decay Modes
Decay ModeIntensity
α (α emission)100%
(double β decay)%

221Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
221.015535637 ± 0.000006134 Da
Mass Number221
G-Factor
-0.0057428571428571 ± 0.00017142857142857
Half Life
25.7 ± 0.5 m
Spin7/2
Quadrupole Moment
-0.47 ± 0.05
Discovery Year1956
Parity+

221Rn Decay Modes
Decay ModeIntensity
β (β decay)78%
α (α emission)22%

222Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
222.017576017 ± 0.000002086 Da
Mass Number222
G-Factor
0
Half Life
3.8215 ± 0.0002 d
Spin0
Quadrupole Moment
0
Discovery Year1899
Parity+

222Rn Decay Modes
Decay ModeIntensity
α (α emission)100%

223Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
223.021889283 ± 0.000008397 Da
Mass Number223
G-Factor
-0.22057142857143 ± 0.0022857142857143
Half Life
24.3 ± 0.4 m
Spin7/2
Quadrupole Moment
0.8 ± 0.08
Discovery Year1964
Parity+

223Rn Decay Modes
Decay ModeIntensity
β (β decay)100%
α (α emission)%

224Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
224.024095803 ± 0.000010536 Da
Mass Number224
G-Factor
0
Half Life
107 ± 3 m
Spin0
Quadrupole Moment
0
Discovery Year1964
Parity+

224Rn Decay Modes
Decay ModeIntensity
β (β decay)100%

225Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
225.028485572 ± 0.000011958 Da
Mass Number225
G-Factor
-0.198 ± 0.0022857142857143
Half Life
4.66 ± 0.04 m
Spin7/2
Quadrupole Moment
0.84 ± 0.08
Discovery Year1969
Parity-

225Rn Decay Modes
Decay ModeIntensity
β (β decay)100%

226Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
226.03086138 ± 0.000011247 Da
Mass Number226
G-Factor
0
Half Life
7.4 ± 0.1 m
Spin0
Quadrupole Moment
0
Discovery Year1969
Parity+

226Rn Decay Modes
Decay ModeIntensity
β (β decay)100%

227Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
227.035304393 ± 0.000015127 Da
Mass Number227
G-Factor
Half Life
20.2 ± 0.4 s
Spin3/2
Quadrupole Moment
Discovery Year1986
Parity+

227Rn Decay Modes
Decay ModeIntensity
β (β decay)100%

228Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
228.037835415 ± 0.000018977 Da
Mass Number228
G-Factor
0
Half Life
65 ± 2 s
Spin0
Quadrupole Moment
0
Discovery Year1989
Parity+

228Rn Decay Modes
Decay ModeIntensity
β (β decay)100%

229Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
229.042257272 ± 0.000014 Da
Mass Number229
G-Factor
Half Life
11.9 ± 1.3 s
Spin5/2
Quadrupole Moment
Discovery Year2009
Parity+

229Rn Decay Modes
Decay ModeIntensity
β (β decay)100%

230Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
230.045271 ± 0.000215 Da
Mass Number230
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year2010
Parity+

230Rn Decay Modes
Decay ModeIntensity
β (β decay)%

231Rn

AbundanceRadioactive ☢️
Relative Atomic Mass
231.049973 ± 0.000322 Da
Mass Number231
G-Factor
Half Life
Spin1/2
Quadrupole Moment
0
Discovery Year2010
Parity+

231Rn Decay Modes
Decay ModeIntensity
β (β decay)%

History

Radon was discovered in 1900 by Friedrich Ernst Dorn in Halle, Germany. He reported some experiments in which he noticed that radium compounds emanate a radioactive gas. In 1910, Sir William Ramsay and Robert Whytlaw-Gray isolated radon, determined its density, and determined that it was the heaviest known gas. The name was derived from radium; called niton at first, from the Latin word nitens meaning shining

DiscoverersFredrich Ernst Dorn
Discovery LocationGermany
Discovery Year1898
Etymology (Name Origin)Variation of the name of another element, radium.
PronunciationRAY-don (English)
Radon is highly radioactive and a carcinogen
Upon condensation, radon glows because of the intense radiation it produces

Uses

Radon is used in hydrologic research that studies the interaction between ground water and streams. Radon has been produced commercially for use in radiation therapy. Radon has been used in implantable seeds, made of gold or glass, primarily used to treat cancers. Used to treat some forms of cancer.

Sources

Formed from the decay of radium in the earths crust.

Abundance
Abundance in Earth's crust
0.0000000000004 mg/kg
Abundance in Oceans
0.0000000000000006 mg/L
Abundance in Human Body
Abundance in Meteor
Abundance in Sun
Abundance in Universe
0 %

Nuclear Screening Constants

1s1.6659
2p4.562
2s22.5864
3d13.4027
3p23.7194
3s24.9149
4d38.0572
4f37.6688
4p36.6988
4s35.85
5d58.647
5p54.029
5s52.107
6p69.9242
6s67.676