Radium

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Animated Radium

History

Radium was discovered in 1898 by Madame Curie in the pitchblende or uraninite of North Bohemia, where it occurs. There is about 1 g of radium in 7 tons of pitchblende. The element was isolated in 1911 by Mme. Curie and Debierne by the electrolysis of a solution of pure radium chloride employing a mercury cathode; on distillation in an atmosphere of hydrogen, this amalgam yielded the pure metal.

Sources

Originally, radium was obtained from the rich pitchblende ore found in Joachimsthal, Bohemia. The carnotite sands of Colorado furnish some radium, but richer ores are found in the Republic of Zaire and the Great Lake region of Canada. Radium is present in all uranium minerals, and could be extracted, if desired, from the extensive wastes of uranium processing. Large uranium deposits are located in Ontario, New Mexico, Utah, Australia, and elsewhere.

Uses

One gram of radium produces about 0.0001 ml (stp) of emanation, or radon gas, per day. This is purged from the radium and sealed in minute tubes, which are used in the treatment of cancer and other diseases. Radium was used in the producing of self-luminous paints, neutron sources, and in medicine for the treatment of disease. Other radioisotopes, such as 60Co, are now being used in place of radium. Some of these sources are much more powerful, and others are safer to use. Radium loses about 1% of its activity in 25 years, being transformed into elements of lower atomic weight. Lead is a final product of disintegration. Stored radium and radium-containing products or minerals should be ventilated to prevent build-up of radon.

General Info

AtomicNumber
88
Symbol
Ra
Name
Radium

Atomic Info

Appearance
AtomicWeight
[226]
Color
007D00
ElectronicConfiguration
[Rn] 7s2
ElectronegativityInPauling
0.9
AtomicRadiusInPM
IonRadiusInPM
148 (+2)
VanDerWaalsRadiusInPM
IEinKJmol
509
EAinKJmol
OxidationStates
2
StandardState
solid
BondingType
metallic
MeltingPoint
973
BoilingPoint
2010
Density
5
State
Alkaline earth metal
DiscoveredYear
1898