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 Number195
Group18
Period6
Blockp
Protons86 p+
Neutrons109 n0
Electrons86 e-
Radon water apparatus P1120815.JPG Radon spectrum visible.png Animated Bohr Model Enhanced Bohr Model Bohr Model Orbital Diagram

Properties

Atomic Radius
Atomic Volume
Covalent Radius
142 pm
Metallic Radius
Ionic Radius
Crystal Radius
Van der Waals radius
220.00000000000003 pm
Density
0.009074 g/cm³
Boiling Point
211.4 K
Melting Point
202 K
Electrons per shell2, 8, 18, 32, 18, 8
Electronegativity
Electrophilicity
Proton Affinity
Electron Affinity
Ionization Potential
10.7485 eV/particle
Heat of Vaporization
18.1 kJ/mol
Heat of Fusion
Heat of Formation
Molar Heat Capacity
20.786 J/(mol K)
Specific Heat Capacity
0.094 J/(g⋅K)
Thermal Conductivity
0.0036 W/(m K)
Gas Basicity
Dipole Polarizability
35 a₀
C6 Dispersion Coefficient
Oxidation States2, 4, 6
Color
Colorless
Crystal Structure (FCC)
Lattice Constant
Bulk Modulus
Electrical Resistivity
Electron Configuration[Xe] 4f14 5d10 6s2 6p6
Magnetic Ordering
Magnetic Susceptibility
PhaseGas
Poisson Ratio
Shear Modulus
Young's Modulus
Allotropes
Alternate Names
Adiabatic Index
Appearance
Electric Conductivity
Critical Pressure
Critical Temperature
Curie Point
Electrical
Hardness
Magnetic Susceptibility
Magnetic
Neel Point
Neutron Cross Section
Neutron Mass Absorption
Gas Phase
Quantum Numbers
Refractive Index
Space Group
Speed of Sound
Superconducting Point
Thermal Expansion
Valence Electrons
Classification
CategoryNoble gases, Noble gases
CAS GroupVIII
IUPAC GroupVIIIA
Glawe Number6
Mendeleev Number117
Pettifor Number6
Geochemical ClassU/Th decay series
Goldschmidt Classsynthetic
Radioactivity
RadioactiveYes ☢️
Decay Mode
Half-Life
Lifetime
Abundance
Abundance in Earth's crust
0.0000000000004 mg/kg
Abundance in Oceans
Abundance in Human Body
Abundance in Meteor
Abundance in Sun
Abundance in Universena

Isotopes of Radon

Stable Isotopes
Unstable Isotopes
195Rn 196Rn 197Rn 198Rn 199Rn 200Rn 201Rn 202Rn 203Rn 204Rn 205Rn 206Rn 207Rn 208Rn 209Rn 210Rn 211Rn 212Rn 213Rn 214Rn 215Rn 216Rn 217Rn 218Rn 219Rn 220Rn 221Rn 222Rn 223Rn 224Rn 225Rn 226Rn 227Rn 228Rn

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
Name OriginVariation of the name of another element, radium.
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.