Radon

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Animated Radon

History

The name was derived from radium; called niton at first, from the Latin word nitens meaning shining.The element was discovered in 1900 by Dorn, who called it radium emanation. In 1908 Ramsay and Gray, who named it niton, isolated the element and determined its density, finding it to be the heaviest known gas. It is essentially inert and occupies the last place in the zero group of gases in the Periodic Table. Since 1923, it has been called radon.

Uses

Radon is still produced for therapeutic use by a few hospitals by pumping it from a radium source and sealing it in minute tubes, called seeds or needles, for application to patient. This practice has been largely discontinued as hospitals can get the seeds directly from suppliers, who make up the seeds with the desired activity for the day of use.

Isotopes

Thirty-nine isotopes are known. Radon-222 is the most common. It has a half-life of 3.823 days and is an alpha emitter. It is estimated that every square mile of soil to a depth of 6 inches contains about 1 g of radium, which releases radon in tiny amounts into the atmosphere. Radon gas can collect in buildings, creating a health risk. The Environmental Protection Agency estimates that responsible for an estimated 20,000 lung cancer deaths each year. More on radon and health. Radon is present in some spring waters, such as those at Hot Springs, Arkansas.

General Info

AtomicNumber
86
Symbol
Rn
Name
Radon

Atomic Info

Appearance
AtomicWeight
[222]
Color
428296
ElectronicConfiguration
[Xe] 4f14 5d10 6s2 6p6
ElectronegativityInPauling
AtomicRadiusInPM
145
IonRadiusInPM
VanDerWaalsRadiusInPM
IEinKJmol
1037
EAinKJmol
OxidationStates
2
StandardState
gas
BondingType
atomic
MeltingPoint
202
BoilingPoint
211
Density
0.01
State
Noble gas
DiscoveredYear
1900