Elementymology & Elements Multidict by Peter van der Krogt
Protactinium
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Multilingual dictionary
Language key
Indo-European
Germanic
Protactinium en de nl fy da no
Protaktinium lb af sv fo
Protaktín is
Italic
Protactinium fr
Protactinio es
Protactínio pt
Protactini ca oc
Protactinio gl
Protoattinio it
Protoatini fur
Protactiniu ro
Protoactiniu mo
Protactiniumu arm
Slavic
Протактиний [protaktinij] ru bg
Протактинiй [protaktynij] uk
Пратактынiй [prataktynij] by
Proaktyn pl
Protaktin kas
Protaktinium cs
Protaktínium sk
Protaktinij sl hr bos
Протоактиниjум [protoaktinijum] sr
Протактиниум [protaktinium] mk
Baltic
Protaktinis lt
Protaktīnijs lv
Prātaktinis sud
Celtic
Protoactiniwm cy
Prótachtainiam ga
Pròtactainiam gd
Protaghtinnium gv
Protoactynyum kw
Protaktiniom br
Other Indo-European
Πρωτακτινιο [prōtaktinio] el
Protaktin sq
Պրոտակտինիում [protaktinium] hy
Indo-Iranian
Протактиний [protaktinij] oss
Uralic
Protaktinium fi
Protaktiinium et
Protaktínium hu
Протактини [protaktini] mok
Altaic
Protaktinyum tr
Протактиний [protaktinij] kk uz
Protaktini' tg
Протактини [protaktini] mn
Other (Europe)
Protaktinioa eu
პროტაქტინიუმი [protak'tiniumi] ka
East- & South-Asia
プロトアクチニウム [purotoakuchiniumu] ja
[pu2 / pok8] zh (mand./cant.)
프로트악티늄 or 프로탁티늄 [peurotagtinyum] ko
Protactini vi
โพรแทกทิเนียม [phrōthaekthiniam] th
Protaktinium ms
புரொட்டக்டினியம் [puroţţakţiniyam] ta
Afro-Asiatic
بروتكتنيوم [brūtaktīniyūm] ar
Protaktinjum mt
פרוטקטיניום [protaktinium] he
Africa
Protaktini sw
Artificial
Protaktinio eo
New names
Proteon (PRT) aen
Gohrjanium dms
Appearance, some properties, a memory peg and a summary of discovery and etymology
Shiny radioactive metal
m.p. <=1600 ºC; <=2912 ºF
b.p. ?
density calculated 15.37 g/cc; 959.52 pound/cubic foot
memory peg

1913 Kasimir Fajans & Otto Göhring
πρωτος (prōtos) + Actinium = first (Greek) + element #89
named by Otto Hahn and Lise Meitner, 1918

History & Etymology

Element #91 was predicted by Д.И. Менделеев (D.I. Mendeleyev) in 1871 and named by him Eka-Tantalum (note) .

Kasimir Fajans The first isotope of Protactinium to be discovered was 234Pam (also called Uranium X2), an ephemerous member of the natural decay series of 238U. This isotope was identified by Kasimir Fajans (1887-1975) and Otto H. Göhring of Karlsruhe in 1913, who called it Brevium (= brief), because of its short half-life (note).

In 1918, two research scientist teams isolated almost simultaneously a more stable isotope (231Pa), of the decay series of 235U. These teams were led by Otto Hahn and Lise Meitner (note), and by Frederick Soddy and John A. Cranston (note). The first team named this isotope Protoactinium, from the Greek πρωτος [prōtos] = first, since its place in the uranium-actinium decay series it is the first before Actinium (it falls apart in Actinium (227Ac) and an α-particle).
The isotope name Protoactinium was shortened in 1949 to Protactinium and became the general name for the element #91.

Historical names of Protactinium Isotopes
Name & Symbol (hist. and modern) First described Notes
Protoactinium Pa 231Pa 1918 O. Hahn & L. Meitner  
Uranium Z U Z 234Pa 1918 O. Hahn  
Uranium X2
Brevium
U X2
Bv
234Pam 1913 K. Fajans & O. Göhring  

John and Gordon Marks suggested in 1994 the name Meitnium (Mt), after Lise Meitner, according to them the discoverer of this element and of the many peculiar properties (especially radioactivity) of the actinides. The Marks brothers found the old names ugly and confusing. They offered alternative names that are equivalent contemporary (at the time and place of discovery) metaphors, both more euphonious and more memorable (note).

Further reading:

  • Mary Elvira Weeks, Discovery of the Elements, comp. rev. by Heny M. Leicester (Easton, Pa.: Journal of Chemical Education, 1968), pp. 783-784, 791-795.
  • Protactinium und Isotope. Gmelins Handbuch der anorganische Chemie, 8. Aufl.; System-Nummer 41 (1952).

Sources

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© Peter van der Krogt