RADIUMS
Noun
radiums
plural of radium
Verb
radiums
Third-person singular simple present indicative form of radium
Anagrams
• marudis, ramidus
Source: Wiktionary
RADIUM
Ra`di*um, n. [NL., fr. L. radius ray.] (Chem.)
Definition: An intensely radioactive metallic element found (combined) in
minute quantities in pitchblende, and various other uranium minerals.
Symbol, Ra; atomic weight, 226.4. Radium was discovered by M. and
Mme. Curie, of Paris, who in 1902 separated compounds of it by a
tedious process from pitchblende. Its compounds color flames carmine
and give a characteristic spectrum. It resembles barium chemically.
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). By reason of these rays they ionize gases, affect
photographic plates, cause sores on the skin, and produce many other
striking effects. Their degree of activity depends on the proportion
of radium present, but not on its state of chemical combination or on
external conditions.The radioactivity of radium is therefore an
atomic property, and is explained as result from a disintegration of
the atom. 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. (The
emanation is a heavy gas, the later products are solids.) These
products are regarded as unstable elements, each with an atomic
weight a little lower than its predecessor. It is possible that lead
is the stable end product. At the same time the light gas helium is
formed; it probably consists of the expelled alpha particles. The
heat effect mentioned above is ascribed to the impacts of these
particles. Radium, in turn, is believed to be formed indirectly by an
immeasurably slow disintegration of uranium.
Source: Webster’s Unabridged Dictionary 1913 Edition