Cranston, John

Radium - the atomic number is 88 and the chemical symbol is Ra. The name derives from the Latin radius for beam or ray because of its tremendous ray-emitting power. It was discovered by the French physicist Pierre Curie and the Polish-bom, French chemist Marie Sklodowska Curie in 1898. It was independently discovered by the British chemists Frederick Soddy and John A. Cranston. It was first isolated in 1910 by Marie Curie and the French chemist Andre-Louis Debieme. The longest half-life associated with this unstable element is 1599 year Ra. 

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. 

F. Soddy, A. S. Russell, and K. Fajans independently predicted the existence of a new member of the uranium series of radioactive elements and that it would occupy the vacant place just below tantalum in the Va group of the periodic system. Protactinium, the patriarch of the actinium series of elements, was discovered in 1917 independently by Otto Hahn and Miss Lise Meitner, by K. Fajans, and by Frederick Soddy, John A. Cranston, and A. Fleck (47, 49, SO). 

Dr. John A. Cranston. Member of the Council of the Society of Chemical Industry. Chairman of the Glasgow Section. He collaborated with Frederick Soddy in important researches on radioactivity, and is an independent discoverer of the element protactinium, Mendeleev s predicted eka-tantalum. 

Three research teams, consisting of German physicists Lise Meitner and Otto Hahn, Polish-American physical chemist Kasimir Fajans and German chemist O. H. Ghhring, and English physicists Frederick Soddy and John A. Cranston, independently and almost simultaneously discover protactinium. 

According to M.E.3Kfeeks and H.M. Leicester, Discovery of the Elements (7th ed.,Jour-nal of Chemical Education, Easton, PA, 1968), perhaps the most authoritative book on the discovery of the elements, protactinium was ako independently discovered by Fajans and Soddy and independently by John Arnold Cranston and Alexander Heck in the same year. 

Cranston, Maurice (1957), John Locke, a Biography. London Longman. 

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