Noddack, Ida (1896–1978)

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Noddack, Ida (1896–1978)

German chemist, co-discoverer of the element Rhenium, who was one of the first to see that the work of the physicist Enrico Fermi might prove that atomic fission was possible. Pronunciation: NOD-ack. Born Ida Eva Tacke in Lackhausen-Wesel am Rhein, Germany, on February 25, 1896; died in 1978; daughter of Adelbert Tacke and Hedwig Danner Tacke; received a diploma from the Technical University of Berlin-Charlottenburg, 1919; received a doctorate from the same school, 1921; married Walter Noddack (a chemist), on May 20, 1926 (died December 7, 1960).

Received an honorary doctorate from the University of Hamburg (1966); recipient of the Liebig Commemorative Medal of the Society of German Chemists (1931); awarded the Scheele Medal of the Swedish Chemical Society (1934), and the Grand Cross of Merit of the Federal Republic of Germany (1966).

Selected writings:

(co-authored with her husband) Das Rhenium (Leipzig: Leopold Voss, 1933); Entwicklung und Aufbau der chemischen Wissenschaft (Freiburg im Breisgau: Hans Ferdinand Schulz Verlag, 1942).

Although she was a co-discover of the element Rhenium and was one of the first scientists to see that the experiments of the physicist Enrico Fermi would make possible the principle of atomic fission, Ida Noddack gained little public acclaim for her work. Biographies of famous scientists would occasionally mention her husband Walter, with whom she conducted most of her research, but her name was generally ignored or commented on only briefly. Fermi even ignored her letter to him in 1934 which pointed out (five years before it was achieved in a laboratory) that his work raised the possibility that atoms could be "split."

She was born Ida Tacke in Lackhausen-Wesel am Rhein, Germany, in 1896, the daughter of Adelbert Tacke and Hedwig Danner Tacke . After earning her doctorate degree at the Technical University of Berlin-Charlottenburg in 1921, Ida worked in the laboratories of the German General Electric Society from 1921 through part of 1924, and in the laboratories of the Siemen and Haisle Company from 1924 through part of 1925. She met her future husband Walter when she assumed a research position in 1925 in the laboratories of the German Research Institute in Berlin. She would remain there for ten years.

Together, the team of Ida Tacke and Walter Noddack concentrated on investigating two of the "missing elements" in the Periodic Table of the Elements compiled by the Russian physicist and chemist Dmitri Mendeleev, elements number 75 and 43. In 1871, Mendeleev had arranged all known elements in order of increasing atomic weight. Where gaps appeared in his table, he left open spaces. These were assumed to be elements which necessarily existed, but which had not yet been discovered. Since he concluded that the chemical and physical characteristics of the elements would recur in a predictable manner as one moved higher and higher in his Periodic Table, the characteristics of the missing elements could be guessed. The challenge was to discover them in nature.

The missing elements number 75 and 43 occupied Group VIIA of Mendeleev's system. In that group, the only known element was manganese. Although manganese was the tenth most common element found in the earth's crust, it became apparent to Ida and Walter that these missing elements had to be very rare, so rare that they might be impossible to detect.

One "missing" element, hafnium, had already been discovered by other scientists, who used X-rays to study minerals containing zirconium. The X-ray results indicated that hafnium could be found in almost every mineral containing zirconium. When the X-ray spectra of manganese ores were examined, however, there were no signs of the missing elements 75 and 43.

Ida and Walter, working with another chemist, Otto Berg, tried a different approach. Assuming that element 75 must appear in very tiny amounts in the ores of other metals, they systematically used X-rays to examine a variety of ores. In 1925, they found the new element in platinum ores and in a mineral called columbite, although they had to enrich its concentration about 100,000 times; it turned out to be so rare that only about one milligram of the element could be found in one ton of the earth's crust.

By processing 600 kilograms of ore from Norway, they were able, by the following year, to produce one gram of the new element. They chose to name the element Rhenium, after the Latin word for the Rhine river, along which Ida had been born.

They described their continuing research on the new element in a book, Das Rhenium, which they published in 1933. They also became the authors of numerous articles in chemical journals, including Zeitschrift fur Inorganische Chemie (Journal for Inorganic Chemistry), Zeitschrift fur physikalische Chemie (Journal for Physical Chemistry), and Die Naturwissenschaften (the Sciences). To rebut critics who questioned whether they had really discovered a new element, they published and read more than 100 scientific papers. After the marriage of Ida and Walter in 1926, many of these appeared under the joint authorship of "Drs. Walter and Ida Noddack."

As the discoverers of Rhenium, they secured a profitable patent on the process of extracting the element from molybedum ores. At first, industry found Rhenium hard to work with, since it is difficult to maintain in its pure form, cannot be worked hot, hardens quickly, and is quick to combine with other elements. But the new element had many practical uses. Rhenium is useful in electrical contacts, where it withstands electrical erosion and outperforms other metals such as tungsten and platinum. Because it is resistant to water, it has been used as parts of magnets in marine engines. Since it has a high melting point and retains its strength at high temperatures, it has been used in high temperature thermocouples. It has also been used in electronic tubes, fountain pen points, and instrument bearings.

The Noddacks also searched for the other "missing element," element number 43. They believed that they had discovered it in 1925 in the mineral niobite. They named the new element Masurium, after a section of Prussia. Their claim was challenged, however, and today credit for discovering the new element—renamed "technetium,"' the name used in modern Periodic Tables—is given to the scientists Emilio Segre and C. Perrier, who found that the element did not exist in nature and could be produced only through artificial means, by using an atomic accelerator called a cyclotron. In fact, Rhenium proved to be the last of the elements to be discovered which was stable and not radioactive.

Ida's joint work with her husband may explain at least some of the lack of public recognition of her work, since their achievements were often listed mainly under her husband's name. They continued their collaboration through the rest of their lives, until his death in 1960, mainly doing photochemical research and experimenting with Walter's idea that every element was present in every mineral, even if the concentration of some elements was too small to detect.

Geographically, her career paralleled his. When he changed university or laboratory positions, she did the same, so that they always were able to work on joint projects. After leaving the German Research Institute in 1935, Ida Noddack worked in the Department of Physical Chemistry at the University of Freiburg from 1935 to 1941. During the early 1940s, both Noddacks continued their research at Bamberg. From 1947 through 1955, they worked in the physical chemistry department of the University of Strasbourg, France, then left in 1956 to work in the Philosophical-Technological High School of Bamberg, where they remained for the rest of their professional careers.

In her most significant project independent of her husband's work, Ida in 1934 wrote an article for the Journal of Applied Chemistry (Angewandte Chemie) which suggested that the physicist Enrico Fermi was misinterpreting the results of experiments in which he bombarded the nuclei of uranium atoms with neutrons. Fermi thought that he was producing new, "transuranium" elements; Ida Noddack suggested that the uranium nuclei were instead "splitting," undergoing a fission process in which isotopes, or variations, of the uranium atom were being produced. She mailed her article to Fermi, but he rejected her perceptive observation. Only five years later, the process of fission was actually accomplished in a German laboratory as the result of the work of Otto Hahn, Fritz Strassman, and Lisa Meitner .

Despite that disappointment, Ida received many honors from fellow scientists. She was awarded the first prize of the Department of Chemistry and Metallurgy at the Technical University of Berlin-Charlottenburg in 1919 for her student work; her research also brought her the Justus-Liebig medal of the Association of German Chemists in 1931 and the Scheele medal of the Swedish Chemical Society in 1933. She was made an honorary member of the German Academy of Natural Science, the Frauenhofer Society, and the Spanish Society for Physics and Chemistry.

During World War II, the Noddacks produced only one major writing, The Development and Growth of the Science of Chemistry. That book appeared to portray them as patriotic Germans who showed no enthusiasm for the National Socialist, or Nazi, government of Germany. They wrote that "long ago, nations discovered that chemistry is a power and a weapon in the lives of people, and most states have made great efforts, to bring their science and chemistry to the level of the Germans." But they added that the "struggle… is fought with the weapons of the intellect," and added that the future would be determined by "education." By implication, military victory in the war was less important than the growth of the intellect and education.

The postwar years brought further honors. In 1966, Ida Noddack was awarded both an honorary doctorate from the University of Hamburg and the Grand Cross of Merit from the German Federal Republic. Her early recognition of the possibility of nuclear fission led American nuclear physicist Glen T. Seaborg to include her 1934 article, in the original German, in a book of landmark scientific publications on uranium and fission. By the time of her death in 1978, a more subtle honor arrived: books on the lives of famous scientists began to give her a separate listing. Beside the listings for "Walter Noddack" also appeared sections on "Ida Tacke Noddack."