86. Radon - Elementymology & Elements Multidict

Elementymology & Elements Multidict

This site comprises 120 pages of text and photos, one for each element, and several pages for access. – For captions or explanatory texts move your mouse over illustrations, links etc.

Radon – Radon – Radon – Radón – ラドン – Радон – 氡
Multilingual dictionary

Radon Latin

— Germanic
Radon Afrikaans
Radon Danish
Radon German
Radon English
Radon Faroese
Radon Frisian (West)
Radon Icelandic
Radon Luxembourgish
Radon Dutch
Radon Norwegian
Radon Swedish

— Italic
Radón Aragonese
Radon Aromanian
Radón Asturian
Radó Catalan
Radón Spanish
Radon French
Radon Friulian
Radon Galician
Radon Italian
Ràdun Lombard
Radon Occitan
Rádon Portuguese
Radon Romanian - Moldovan

— Slavic
Радон [Radon] Bulgarian
Radon Bosnian
Радон [radon] Belarusian
Radon Czech
Radon Croatian
Redón Kashubian
Радон [Radon] Macedonian
Radon Polish
Радон [Radon] Russian
Radon Slovak
Radon Slovenian
Радон [Radon] Serbian
Радон [radon] Ukrainian

— Baltic
Radonas Lithuanian
Radons Latvian
Raduons Samogitian

— Celtic
Radon Breton
Radon Welsh
Radón Gaelic (Irish)
Radon Gaelic (Scottish)
Raadon Gaelic (Manx)
Radon Cornish

— Other Indo-European
Ραδονιο [radonio] Greek
Ռադոն [ŗadon] Armenian
Radon[i] Albanian

— Indo-Iranian/Iranian
Radon Kurdish
Радон [radon] Ossetian
Радон [Radon] Tajik

— Indo-Iranian/Indo-Aryan
রেডন [reḍana] Bengali
رادون [radwn] Persian
રેડૉનનો [reḍonano] Gujarati
रेडन [reḍana] Hindi

Radoon Estonian
Radon Finnish
Radon Hungarian
Радон [Radon] Komi
Радон [Radon] Mari
Радон [radon] Moksha
Radoon Võro

Radon Azerbaijani
Радон [Radon] Chuvash
Радон [radon] Kazakh
Радон [Radon] Kyrgyz
Радон [radon] Mongolian
Radon Turkish
رادون [radon] Uyghur
Radon Uzbek

Other (Europe)
Radona Basque
რადონი [radoni] Georgian

رادون [rādūn] Arabic
רדון [radon] Hebrew
Radon Maltese

Tûng (氡) Hakka
ラドン [radon] Japanese
라돈 [radon] Korean
เรดอน [rēdon] Thai
Rađơn Vietnamese
[dong1 / dung1] Chinese

Radon Cebuano
Radon Indonesian
Radon Māori
Radon Malay

Other Asiatic
റഡോണ്‍ [ṟaḍōṇ] Malayalam
ரேடோன் [rēţōṉ] Tamil

Lado Lingala
Radone Sesotho
Radoni Swahili

Radón Nahuatl

Radun Quechua

Radoni Sranan Tongo

Radono Esperanto

New names
Radon Atomic Elements
Kilonoble Dorseyville
memory peg

Heavy radioactive gas
melting point -71 °C; -96 °F
boiling point -62 °C; -79 °F
density 0.0097 g/cc; 0.61 pounds/cubic foot
1899 Pierre & Marie Curie, France
radium = element #88

History & Etymology

In 1899, Robert B. Owens (1870-), professor of electrical engineering at McGill University in Montreal, was trying to measure radiation from Thorium. Every time he made a measurement, he got a different result. Together with Ernest Rutherford (1871-1937), also teaching at McGill University, he studied this phenomenon and they observed that

"the radiation from thorium oxide was not constant, but varied in a most capricious manner." whereas "all the compounds of Uranium give out a radiation which is remarkably constant" (note).
Rutherford concluded that Thorium compounds continuously emit a radioactive gas which retain their radioactive powers for several minutes. He called this gas "emanation", from Latin "emanare" - to elapse and "emanatio" - expiration (note), hence Thorium Emanation (Th Em).

In the same year Pierre and Marie Curie observed a similar phenomenon with Radium, except that the "gas" emitted by Radium remained radioactive for a month (note). In 1900, Friedrich Ernst Dorn (1848-1916) confirmed the findings of Rutherford and the Curies (note), thus Radium Emanation (Ra Em). Most standard sources on the chemical elements list Dorn as the discoverer in 1900. In fact he had merely repeated the Curies’ experiment with more active Radium compounds.

In fact that the emanations emitted by Radium are a radioactive gas was clearly demonstrated by Rutherford and Brooks in 1901, though they were careful to give credit to the prior observations of the Curies (note).

In 1903, Fritz Giesel observed emanations from Emanium (note) and in the same year André-Louis Debierne (1874-1949) from Actinium (note). In 1906, when was concluded that Giesel's Emanium was identical with Debierne's Actinium, both emanations were therefore called Actinium Emanation (Ac Em).

The likeness of the spectra of these three gases with those of Argon, Krypton and Xenon, and its chemical inertia suggested that the "emanations" could contain a new element from the noble gases family. Several names were suggested:

  Radium Emanation Thorium Emanation Actinium Emanation
Ramsay & Collie, 1904 Exradio Exthorio Exactinio
Perrin, 1919 Radeon Thoreon Actineon
Schmidt, 1918 Radon Thoron Akton
Adams, 1920 Radon Thoron Actinon

Sir William Ramsay and J. Norman Collie wrote about their suggestion in 1904:
"It may be remembered that, at the Chemical Congress held in Paris in 1900, it was suggested that no element should receive a name until its spectrum had been mapped. (...) The «emanation from radium», however, is a cumbrous expression, and sufficient evidence has now been accumulated that it is an element, accepting that word in the usual sense. It is true that it is only a transient element, and ought in justice to be called a compound; but of what? It stands on a wholly different plane to any known compound (...) It is a gas; it follows Boyle's law; (...) it resembles the gases of the argon series in its indifference to chemical reagents (...) Now, it appears advisable to devise a name which should recall its source, and, at the same time, by its termination, express the radical difference which undoubtedly exists between it and other elements. As it is derived from radium, why not name it simply «exradio»? Should it be found that the emanation, which is supposed to be evolved from thorium, is really due to that element, and not to some other element mixed with thorium in exceedingly small amount, a similar name could be given, namely «exthorio». If the existence of actinium as a definite element is established, its emanation would appropriately be named «exactinio»." (note)
In 1910 Sir William Ramsay, whose 1904 suggestion was not followed, together with Robert W. Whytlaw-Gray again tried to change the cumbersome name. "L'expression l'émanation du radium est fort incommode," they wrote and suggested the new name Niton (symbol Ni), from Latin "nitens" (shining) (note). With this name he obviously desired to emphasize the property of gas to cause the phosphorescence of some substances. In 1912 this name was accepted by the International Commission for Atomic Weights. However, until 1923 the three gases were usually named Radium Emanation, Thorium Emanation, and Actinium Emanation.
(John and Gordon Marks suggested in 1994 Ramsay's name Niton (Nt) for the element. 'Radon' is short for 'radium emanation', Nt-222, and is thus merely an isotope of niton. Similarly thoron is Nt-220 and actinon is Nt-219. We do not refer to hydrogen as 'protium') (note).)

In 1923, the International Committee for Chemical Elements and the Union internationale de la chimie pure et appliquée chose for the names proposed by Schmidt and Adams: Radon, Thoron, and Actinon, with symbols Rn, Tn, and An.

Later, when isotopes were numbered instead of named, the name of the element became Radon.

Historical names of Radon isotopes
Name & Symbol (hist. and modern) First described Notes
Radium Emanation
1912: Niton, 1923: Radon
Ra Em
Ni, Rn
222Rn 1899/
Pierre & Marie Curie
Friedrich E. Dorn
Thorium Emanation
1923: Thoron
Th Em
220Rn 1900 Ernest Rutherford  
Actinium Emanation
1923: Actinon
Ac Em
219Rn 1903 A. Debierne and Friedrich O. Giesel  

Further reading
  • McGill Rutherford Museum, Emanations from Thorium and Radium (on line).
  • Edelgase. Gmelins Handbuch der anorganische Chemie, 8. Aufl.; System-Nummer 1 (1926).
  • David J. Brenner, Rutherford, the Curies, and Radon (PDF on line)
  • Was ist Radon? (on line).

Sources Index of Persons Index of Alleged Elements