Radon is a chemical element wi seembol Rn an atomic nummer 86. It is a radioactive, colourless, odorless, tasteless[2] noble gas, occurrin naiturally as an indirect decay product o uranium or thorium. Its maist stable isotope, 222Rn, haes a hauf-life o 3.8 days. Radon is ane o the densest substances that remains a gas unner normal condeetions. It is the anly gas unner normal condeetions that anly haes radioactive isotopes, an is considered a heal hazard due tae its radioactivity an aa. Intense radioactivity haes an aa hindered chemical studies o radon an anly a few compoonds are kent.

Radon, 86Rn
Radon
Pronunciation/ˈrdɒn/ (RAY-don)
Appearancecolourless gas
Mass number[222]
Radon in the periodic cairt
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Airn Cobalt Nickel Capper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Siller (element) Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gowd Mercur (element) Thallium Leid (element) Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Ununtrium Flerovium Ununpentium Livermorium Ununseptium Ununoctium
Xe

Rn

Uuo
astatineradonfrancium
Atomic nummer (Z)86
Groupgroup 18 (noble gases)
Periodperiod 6
Blockp-block
Element category  Noble gas
Electron confeeguration[Xe] 4f14 5d10 6s2 6p6
Electrons per shell2, 8, 18, 32, 18, 8
Pheesical properties
Phase at STPgas
Meltin pynt202 K ​(−71 °C, ​−96 °F)
Bylin pynt211.5 K ​(−61.7 °C, ​−79.1 °F)
Density (at STP)9.73 g/L
whan liquid (at b.p.)4.4 g/cm3
Creetical pynt377 K, 6.28[1] MPa
Heat o fusion3.247 kJ/mol
Heat o vapourisation18.10 kJ/mol
Molar heat capacity5R/2 = 20.786 J/(mol·K)
Vapour pressur
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 110 121 134 152 176 211
Atomic properties
Oxidation states0, +2, +6
ElectronegativityPauling scale: 2.2
Covalent radius150 pm
Van der Waals radius220 pm
Colour lines in a spectral range
Colour lines in a spectral range
Spectral lines o radon
Ither properties
Creestal structurface-centred cubic (fcc)
Face-centered cubic creestal structur for radon
Thermal conductivity3.61 m W/(m·K)
Magnetic orderinnon-magnetic
CAS Nummer10043-92-2
History
DiskiveryFriedrich Ernst Dorn (1898)
First isolationWilliam Ramsay an Robert Whytlaw-Gray (1910)
Main isotopes o radon
Iso­tope Abun­dance Hauf-life (t1/2) Decay mode Pro­duct
210Rn syn 2.4 h α 206Po
211Rn syn 14.6 h ε 211At
α 207Po
222Rn trace 3.8235 d α 218Po
224Rn syn 1.8 h β 224Fr
| references

References eedit

  1. Haynes, William M., ed. (2011). CRC Handbook of Chemistry and Physics (92nt ed.). CRC Press. p. 4.122. ISBN 1439855110.
  2. "A Citizen's Guide to Radon | Radon | US EPA". Epa.gov. 5 August 2010. Retrieved 28 Apryle 2012.