After the Latin name for which modern European capital is the element Lutetium named?
Lutetium producing hafnium isotopes. The element also has 42 nuclear isomers, with masses of 150, 151, 153–162, 166–180 (not every mass number corresponds to only one isomer). The most stable of them are lutetium-177m, with half-life of 160.4 days and lutetium-174m, with half-life of 142 days; this is longer than half-lives of the ground states of all radioactive lutetium isotopes, except only for lutetium-173, 174, and 176. Lutetium, derived from the Latin "Lutetia" (Paris), was independently discovered in 1907 by French scientist Georges Urbain, Austrian mineralogist Baron Carl Auer von Welsbach, and American chemist Charles James. They found it as an
Lutetium of lutetium from Marignac's ytterbium was first described by Urbain; after Urbain's names were recognized, neoytterbium was reverted to ytterbium. Until the 1950s, some German-speaking chemists called lutetium by Welsbach's name, "cassiopeium"; in 1949, the spelling of element 71 was changed to lutetium. The reason for this was that Welsbach's 1907 samples of lutetium had been pure, while Urbain's 1907 samples only contained traces of lutetium. This later misled Urbain into thinking that he had discovered element 72, which he named celtium, which was actually very pure lutetium. The later discrediting of Urbain's work on element 72 led to a