(isim) radyum

Türkisch - Englisch

Definition von (isim) radyum im Türkisch Englisch wörterbuch

radium

a radioactive metallic chemical element (symbol Ra) with an atomic number of 88

Symbol, Ra; atomic weight, 226

This breaking up occurs in at least seven stages; the successive main products have been studied and are called radium emanation or exradio, radium A, radium B, radium C, etc

Radium was discovered by M

Curie, of Paris, who in 1902 separated compounds of it by a tedious process from pitchblende

The emanation is a heavy gas, the later products are solids

Radium preparations are remarkable for maintaining themselves at a higher temperature than their surroundings, and for their radiations, which are of three kinds: alpha rays, beta rays, and gamma rays (see these terms)

At the same time the light gas helium is formed; it probably consists of the expelled alpha particles

The radioactivity of radium is therefore an atomic property, and is explained as result from a disintegration of the atom

an intensely radioactive metallic element that occurs in minute amounts in uranium ores

Radium, in turn, is believed to be formed indirectly by an immeasurably slow disintegration of uranium

It is possible that lead is the stable end product

It was discovered by Marie Curie and her husband, Pierre Curie, in 1898 and isolated by 1910. All its isotopes are radioactive (see radioactivity). Radium does not occur free in nature but occurs in natural ores such as pitchblende as a disintegration product of radioactive decay of heavier elements, including uranium. Chemically it is highly reactive and has valence 2 in all of its compounds. Its use in medicine (see radiation therapy; radiology; nuclear medicine) has declined because of its cost, and its use in consumer goods (to illuminate watch and clock hands and numbers, as well as instrument dials) was halted because it can cause radiation injury. It is still used for some radiography and as a source of neutrons

Their degree of activity depends on the proportion of radium present, but not on its state of chemical combination or on external conditions

Its compounds color flames carmine and give a characteristic spectrum

An intensely radioactive metallic element found (combined) in minute quantities in pitchblende, and various other uranium minerals

{i} (Ra) radioactive metallic chemical element

These products are regarded as unstable elements, each with an atomic weight a little lower than its predecessor

and Mme

Silbentrennung

(i·sim) rad·yum