Masataka Ogawa

Masataka Ogawa (Japanese小川 正 孝; * February 21, 1865; † July 11, 1930 ) was a Japanese chemist. He became known by the supposed discovery of the element with the atomic number 43, which was to be later known as technetium.

Life

After completing his studies in chemistry at the University of Tokyo he was sent by the Japanese government to London to further experience with a Nobel Prize winner William Ramsay. There he worked on the analysis of the rare mineral thorianite, which was found in 1904 in Ceylon. From this he isolated an unknown substance. Because of the line spectrum he postulated to have found a new element. Ramsay suggested it after Ogawa's home before the name Nipponium.

After his return to Japan in 1906 he continued to study the substance and measured her a equivalent weight of about 50 to. From this he postulated to have found the missing element in the periodic table between molybdenum and ruthenium. In 1910 he was honored by the Chemical Society of Japan for his discovery, although its results could not be replicated. International ran his claim soon forgotten.

From 1911 he taught as a professor at Tohoku University, whose rector in 1919.

Recent studies suggest that Ogawa had actually rhenium with the atomic number 75 isolated. Both elements were detected in 1925 by Walter and Ida Tacke Noddack, this is not recognized for element 43 - until 1937 succeeded Emilio Segrè the undisputed evidence.