radium
radium
Symbol: Ra
Atomic number: 88
Atomic weight: (226)
Radioactive metallic transuranic element, belongs to group 2 of the periodic table. Most stable isotope, Ra-226 has a half-life of 1602 years, which decays into radon. Isolated from pitchblende in 1898 Marie and Pierre Curie.

Elements of periodic system. 2013.

  • RADIUM — En 1898, quelques mois après avoir découvert le polonium, Pierre et Marie Curie et leur collaborateur Gustave Bémont, poursuivant l’étude du fractionnement de la pechblende de Joachimsthal (aujourd’hui Jáchymov, en République tchèque), purent… …   Encyclopédie Universelle

  • Radium — (pronEng|ˈreɪdiəm) is a radioactive chemical element which has the symbol Ra and atomic number 88. Its appearance is almost pure white, but it readily oxidizes on exposure to air, turning black. Radium is an alkaline earth metal that is found in… …   Wikipedia

  • Radium — Ra di*um (r[=a] d[i^]*[u^]m), n. [NL., fr. L. radius ray.] (Chem.) 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… …   The Collaborative International Dictionary of English

  • Radium — Sn (radioaktives Erdalkalimetall) per. Wortschatz fach. (20. Jh.) Neoklassische Bildung. Entdeckt und bezeichnet von den französischen Physikern M. und P. Curie. Zu l. radius Strahl als das Strahlende .    Ebenso nndl. radium, ne. radium, nfrz.… …   Etymologisches Wörterbuch der deutschen sprache

  • Radium — Студийный альбом Ruoska Дата выпуска 22 марта 2005 Жанр Industrial metal Neue Deutsche Härte Лейбл Kråklund Records П …   Википедия

  • Radium — Radium, KS U.S. city in Kansas Population (2000): 40 Housing Units (2000): 19 Land area (2000): 0.041442 sq. miles (0.107335 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 0.041442 sq. miles (0.107335 sq. km)… …   StarDict's U.S. Gazetteer Places

  • Radĭum — Ra, chemisches Element, ist bisher nur als Begleiter des Urans in Mineralien aufgefunden worden, und zwar scheint der Gehalt der Gesteine an R. direkt von ihrem Urangehalt abhängig zu sein. Wahrscheinlich ist R. spurenweise überall in der festen… …   Meyers Großes Konversations-Lexikon

  • radium — RÁDIUM s.n. v. radiu. Trimis de LauraGellner, 13.09.2007. Sursa: DEX 98  RÁDIUM s.n. v. radiu. Trimis de LauraGellner, 13.09.2007. Sursa: DN …   Dicționar Român

  • radium — / radjum/ s.m. [lat. scient. Radium, der. del lat. class. radius raggio ]. (chim.) [elemento chimico di simbolo Ra] ▶◀ radio …   Enciclopedia Italiana

  • radium — (n.) radioactive metallic element, 1899, from Fr. radium, named 1898 after identification by Marie Curie and her husband, formed in Modern Latin from L. radius ray (see RADIUS (Cf. radius)). So called for its power of emitting energy in the form… …   Etymology dictionary

  • radium — [rā′dē əm] n. [ModL < L radius, ray (see RADIUS) + IUM: so named (1898) by P. & M. Curie & G. Bémont, because it emits rays] a radioactive, metallic chemical element, one of the alkaline earth metals, found in very small amounts in pitchblende …   English World dictionary