Gohring, Otto

It was first identified and named brevium, meaning brief, by Kasimir Fajans and O. H. Gohring in 1913 because of its extremely short half-life. In 1918 Otto Hahn (1879—1968) and Lise Meitner (1878-1968) independently discovered a new radioactive element that decayed from uranium into (actinium). Other researchers named it uranium X2. It was not until 1918 that researchers were able to identify independently more of the elements properties and declare it as the new element 91 that was then named protactinium. This is another case in which several researchers may have discovered the same element. Some references continue to give credit for protactinium s discovery to Frederich Soddy (1877—1956) and John A. Cranston (dates unknown), as well as to Hahn and Meitner. 

Protactinium Pa 1913 (Berlin, Germany) 1918 (Berlin, Germany) Kasimir Fajans (Polish) and Otto Gohring (German) Otto Hahn (German), Lise Meitner (Austrian), and John Cranston and Frederick Soddy (both British) 311... 

Pa, protactinium, was first identified in 1913 in the decay products of U-238 as the Pa-234 isotope (6.7 h) by Kasimir Fajans and Otto H. Gohring. In 1916, two groups, Otto Hahn and Lisa Meitner, and Frederick Soddy and John A. Cranston, found Pa-231 (10 years) as a decay product of U-235. This isotope is the parent of Ac-227 in the U-235 decay series, hence it was named protactinium (before actinium). Isolation from U extraction sludges yielded over 100 g in 1960. 

In 1918, another isotope of element number 91 was discovered by German physicists Lise Meitner (1878-1968) and Otto Hahn (1879— 1968). This isotope had a half life of 32,500 years. It was much easier to study than the isotope discovered by Fajans and Gohring. 

An isotope of protactinium (having mass number 234 and a half-life of 1.1 minutes) was first identified by Kasimir Fajans and O. Gohring in 1913 as a short-lived member of the naturally occurring decay series and was given the name brevium, meaning brief The existence of protactinium was confirmed in 1918 when another isotope of protactinium (of mass 231 and a half-life of 3.3 X 10 years) was studied independendy by Otto Hahn and... 

H. Gohr and Otto Scholl, Beitr. Klin. Tuberk., B102,29 (1949). 

Discovery Protactinium was identified by Fajans and Gohring in Karlsruhe in 1913, who named the new element brevium. They had discovered the isotope Pa with a half-life of 5.70 h. Lise Meitner at the Kaiser-Wilhelm Institute for Chemistry in Berlin separated the oxide of a more long-lived isotope from pitchblende (mixed with tantalum oxide). She published the news in 1918 together with Otto Hahn. The new element was discovered independently in the same year by F. Soddy, J. A. Cranston and A. Fleck in Glasgow. The name protactinium was selected because it was recognized as the prototype for actinium. The element was first isolated by Aristid V. Crosse in 1934. He prepared 2 mg of the metal. 

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