Radon

Symbol	Rn
Atomnummer	86
Gruppe	18 (Ædelgasser)
Periode	6
Blok	p
Klassifikation	Ædelgasser

Udseende	Colorless gas, occasionally glows green or red in discharge tubes
Farve	Farveløs

Antal protoner	86 p+
Antal neutroner	136 n0
Antal elektroner	86 e-

Fra Wikipedia, den gratis encyklopædiRadon er et grundstof med atomnummer 86 og symbol Rn i det periodiske system. Radon, der dannes fra radiums henfald, er en farveløs naturligt forekommende ædelgas. Den er en af de tungeste stoffer, der under normale forhold er gasformig og øger risikoen for lungekræft. Radons farlighed ser ud til at være mangedobblet hos rygere. Alle radons isotoper er radioaktive. Den mest stabile isotop, ²²²Rn, har en halveringstid på 3,8 dage og anvendes til strålebehandling. Det er de isotoper radon henfalder til, som er kræftfremkaldende.

Fase ved STP	Gas
Massefylde	9.73 g/cm3
Atommasse	222 u

Smeltepunkt	202 K -71.15 °C -96.07 °F
Kogepunkt	211.5 K -61.65 °C -78.97 °F
Fordampningsvarme	16.4 kJ/mol

Elektronegativitet (Pauling Scale)	2.2
Elektronaffinitet	-68 kJ/mol
Oxidationstrin	0, +2, +6 ()
Ioniseringsenergier	1037 kJ/mol

Elektronkonfiguration Kortfattet konfiguration	[Xe] 4f14 5d10 6s2 6p6
Elektronkonfiguration Fuld konfiguration	1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 6s2 6p6
Elektronkonfigurationsdiagram	1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 6s2 6p6
Elektroner pr. Skal	2, 8, 18, 32, 18, 8
Valenselektroner	8
Valency-elektroner	0
Bohrs atommodel	Figur: Skaldiagram af Radon (Rn) atom.
Orbital diagram 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 6s 6p

Opdaget	Ernest Rutherford, Robert Bowie Owens (1899)
Første isolation	William Ramsay, Robert Whytlaw-Gray (1910)
Opdagelse af radon Radon was the fifth radioactive element to be discovered, in 1899 by Ernest Rutherford and Robert B. Owens at McGill University in Montreal, after uranium, thorium, radium, and polonium. In 1899, Pierre and Marie Curie observed that the gas emitted by radium remained radioactive for a month. Later that year, Rutherford and Owens noticed variations when trying to measure radiation from thorium oxide. Rutherford noticed that the compounds of thorium continuously emit a radioactive gas that remains radioactive for several minutes, and called this gas "emanation" (from Latin: emanare, to flow out, and emanatio, expiration), and later "thorium emanation" ("Th Em"). In 1900, Friedrich Ernst Dorn reported some experiments in which he noticed that radium compounds emanate a radioactive gas he named "radium emanation" ("Ra Em"). In 1901, Rutherford and Harriet Brooks demonstrated that the emanations are radioactive, but credited the Curies for the discovery of the element. In 1903, similar emanations were observed from actinium by André-Louis Debierne, and were called "actinium emanation" ("Ac Em"). In 1909, Ramsay and Robert Whytlaw-Gray isolated radon and determined its melting temperature and approximate density. In 1910, they determined that it was the heaviest known gas.

Original word	radius
Language of origin	Latin
Name source	Egenskaber
Meaning	“From radium”
Naming The name is derived from radium: radon was originally called 'radium emanation' before being recognised as a separate element.

CAS Number	10043-92-2
ChemSpider ID	23240
EC number	233-146-0
PubChem CID Number	24857