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Berg. Otto

Rhenium - the atomic number is 75 and the chemical symbol is Re. The name derives from the Latin rhenus for the Rhine river in Germany . It was discovered by x-ray spectroscopy in 1925 by the German chemists, Walter Noddack, Ida Tacke and Otto Berg. [Pg.18]

Rhenium Re 1925 (Berlin, Germany) Walter Noddack, Ida Tacke Noddack and Otto Berg (all German) 155... [Pg.399]

German chemists Ida Tacke, Walter Nodack, and Otto Carl Berg Extremely rare useful in making metal alloys wear resistant, especially those used to make electrical contacts. [Pg.247]

Two new elements of the manganese group, numbers 43 (eka-manganese) and 75 (dwi-manganese), were announced in June, 1925, by the German chemists Dr. Walter Noddack and Dr. Ida Tacke of the Physico-Technical Testing Office in Berlin and Dr. Otto Berg of the Werner-Siemens Laboratory. The discovery was not accidental, but the... [Pg.851]

Rhenium was discovered by a German research team that included Walter Noddack (1893-1960), IdaTacke (1896-1979), and Otto Berg. These scientists knew that there were several empty boxes in the periodic table that represented elements that had not yet been discovered. The periodic table is a chart that shows how chemical elements are related to one another. In 1925, the German team announced that they had found two elements. They were correct about one (element number 75) but wrong about the other (element number 43). [Pg.491]

German chemists Walter Noddack, Ida Tacke, and Otto Berg rediscover and name rhenium. [Pg.778]

The name is from the Rhineland in Germany. In 1908, the Japanese chemist Masataka Ogawa (1865-1933) discovered this element and called it nip-ponium, but he incorrectly assigned it to periodical space 43. In 1925, the research team of Walter Noddack (1893-1960), Ida Eva Tacke (1896-1978, later Ida Noddack), and Otto Berg (1873- ) extracted 1 g of rhenium from molybdenite ore and correctly characterized its properties. Rhenium is relatively rare. Its main uses are in laboratory equipment such as spectrographs, in filaments for photoflash lamps, and in some specialty electrical equipment. [Pg.147]

The name comes from the Greek technetos, meaning artificial. There were claims to have discovered element 43 as early as 1877, based on the predicted existence of eka-manganese. In 1925, Walter Noddack, Ida Tacke, and Otto Berg claimed to have found the element, calling it masurium. Definitive proof was made by Emilio G. Segre (1905-1989) in 1937, who was studying a small piece of radioactive molybdenum created at the Berkeley cyclotron. [Pg.147]

In 1925, when Ida Noddack-Tacke, Walter Noddack, and Otto Berg first claimed the discovery of element 75, rhenium (see chapter 3), their work was dismissed because of the extremely minute quantity reported. Their case was solidly proven in 1928 when they were able to accumulate a gram of the metal. In 1925, they had also claimed discovery of the missing element 43 in samples of uranium-rich ores. However, this was also dismissed because of the extremely minute quantity evident from the weak X-ray emission line. In contrast to their subsequent success with rhenium, they could never isolate a quantity to support their claim for element 43. In recent years, evidence does appear to suggest that they probably were correct. Definitive proof was produced by Carlo Perrier (1886-1948) and Emilio Segre (1905-89), who bombarded molybdenum with neutrons. This was the first new element to be produced artificially. [Pg.114]

Otto van den Berg, Michael Wubbenhorst, Stephen J. Picken, Wolter F. Jager, (2005). [Pg.290]

Rhenium 1925 Walter Noddack (Germany), Ida Tacke (Germany), and Otto Berg (Germany) ... [Pg.247]

Discovery The existence of rhenium was predicted in 1871 by Mendelejev, who named it dvi-man-ganese. Walter Noddack, Ida Tacke and Otto Berg discovered rhenium in Beriin in 1925. [Pg.655]

Walter Noddack and Ida Tacke (Mn and Mrs. Noddack) started systematic experimental attempts to find elements 43 and 75 in 1922. They worked partly at the physical-chemical institution at the University of Berlin, partly at the Physico-Technical Testing Institute (Physikahsch-Technische Reichsanstalt). Otto Berg at Siemens Halske took part in the work as an expert on spectroscopic investigations. [Pg.660]


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See also in sourсe #XX -- [ Pg.4 , Pg.80 ]

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See also in sourсe #XX -- [ Pg.648 , Pg.655 , Pg.660 ]




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