Radon

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
HydrogenHelium
LithiumBerylliumBoronCarbonNitrogenOxygenFluorineNeon
SodiumMagnesiumAluminiumSiliconPhosphorusSulfurChlorineArgon
PotassiumCalciumScandiumTitaniumVanadiumChromiumManganeseAirnCobaltNickelCapperZincGalliumGermaniumArsenicSeleniumBromineKrypton
RubidiumStrontiumYttriumZirconiumNiobiumMolybdenumTechnetiumRutheniumRhodiumPalladiumSiller (element)CadmiumIndiumTinAntimonyTelluriumIodineXenon
CaesiumBariumLanthanumCeriumPraseodymiumNeodymiumPromethiumSamariumEuropiumGadoliniumTerbiumDysprosiumHolmiumErbiumThuliumYtterbiumLutetiumHafniumTantalumTungstenRheniumOsmiumIridiumPlatinumGowdMercur (element)ThalliumLeid (element)BismuthPoloniumAstatineRadon
FranciumRadiumActiniumThoriumProtactiniumUraniumNeptuniumPlutoniumAmericiumCuriumBerkeliumCaliforniumEinsteiniumFermiumMendeleviumNobeliumLawrenciumRutherfordiumDubniumSeaborgiumBohriumHassiumMeitneriumDarmstadtiumRoentgeniumCoperniciumUnuntriumFleroviumUnunpentiumLivermoriumUnunseptiumUnunoctium
Xe

Rn

Uuo
astatine ← radon → francium
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)1101001 k10 k100 k
at T (K)110121134152176211
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 structur ​face-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
Iso­topeAbun­danceHauf-life (t1/2)Decay modePro­duct
210Rnsyn2.4 hα206Po
211Rnsyn14.6 hε211At
α207Po
222Rntrace3.8235 dα218Po
224Rnsyn1.8 hβ224Fr
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References