Tag: Technetium

Pique the Geek 20120429: Technetium, An odd Element

Last week a commenter suggested this topic, and I am always happy to get reader feedback and try to honor requests.  Technetium is one of only two elements with an atomic number (Z) less than 82 (Z =  43) without a stable isotope, the other one being promethium, with Z = 61.  Dimitri Mendeleev predicted this element after he had perfected the Periodic Table of the elements in 1871.  He called it ekamanganese since it occupies the place in the table one row under manganese.

Technetium was claimed to have been discovered over and over, and credit to its discovery goes to Emilio Segre and Carlo Perrier in 1936.  It was discovered in a foil that Ernest Lawrence had given Segre that was composed of molybdenum.  Some of the molybdenum had been transmuted into technetium, and the Italian team confirmed this.