Noddack , Walter

(1893–1960) German chemist

Noddack was born in Berlin and educated at the university there, obtaining his doctorate in 1920. He worked first at the Physikalische Technische Reichsanstadt, the German national physical laboratory, until 1935, and then held chairs in physical chemistry at Freiburg and Strasbourg until, in 1946, he moved to Bamberg. Noddack taught chemistry at the local Hochschule there before serving (1955–60) as the director of the Bamberg Institute of Geochemistry.

In 1926, in collaboration with his wife Ida Tacke, Noddack discovered the element rhenium. They thought that they had found element 43, which they named ‘masurium’. In fact this element was correctly identified in 1937 by Emilio Segrè, who named it technetium.

Noddack is also remembered for arguing for a concept he calledallgegenwartskonzentration or, literally, omnipresent concentration. This idea, somewhat reminiscent of the early Greek philosopher Anaxagoras, assumed that every mineral actually contained every element. The reason they could not all be detected was, of course, because they existed in too small quantities.