Ida Tacke Noddack | Biography

Working with fellow chemist Walter Noddack (her future husband) and X-ray specialist Otto Berg , Ida Tacke discovered element 75 , rhenium, in 1925, thus solving one of the mysteries of the periodic table of elements introduced by Russian chemist Dmitri Ivanovich Mendeleev in 1869. Ida Tacke Noddack's continuing study of the periodic table also led her to be the first to suggest in 1934 that physicist Enrico Fermi had not made a new element in an experiment with uranium as he thought, but instead had discovered nuclear fission. Her prediction was not verified until 1939.

Ida Tacke was born in Germany on February 25, 1896 and studied at the Technical University in Berlin, where she received the first prize for chemistry and metallurgy in 1919. In 1921, soon after receiving her doctorate, she set out to isolate two of the elements that Mendeleev had predicted when he proposed the Periodic System and displayed all known elements in a format now called the periodic table. Mendeleev had left blank spaces on his table for several elements that he expected to exist but that had not been identified. Two of these, elements 43 and 75, were located in Group VII under manganese.

Assuming that these elements would be similar in their properties to manganese, scientists had been searching for them in manganese ores. Tacke and Walter Noddack, who headed the chemical laboratory at the Physico-Technical Research Agency in Berlin, focused instead on the lateral neighbors of the missing elements, molybdenum, tungsten, osmium, and ruthenium. With the assistance of Otto Berg of the Werner-Siemens Laboratory, who provided expertise in analyzing the X-ray spectra of substances, Tacke and Noddack isolated element 75 in 1925 and named it rhenium, from Rhenus, Latin for the Rhine, an important river in their native Germany. It took them another year to isolate a single gram of the element from 660 kilograms of molybdenite ore. They also believed they had discovered traces of element 43, which they dubbed masurium . Later research, however, did not confirm their results. Now known as technetium, element 43 has never been found in nature, although it has been produced artificially.

In 1926, Ida Tacke married Walter Noddack. They would work together in their research until Walter Noddack's death in 1960, and together would publish some one hundred scientific papers. The Noddacks were awarded the Leibig Medal of the German Chemical Society in 1934 for their discovery of rhenium.

In 1934 Ida Noddack challenged the conclusions of Enrico Fermi and his group that they had produced transuranium elements, artificial elements heavier than uranium, when they bombarded uranium atoms with subatomic particles called neutrons. Although other scientists agreed with Fermi, Noddack suggested he had split uranium atoms into isotopes of known elements rather than added to uranium atoms to produce heavier, unknown elements. She had no research to support her theory, however, and for five years her hypothesis that atomic nuclei had been split was virtually ignored. "Her suggestion was so out of line with the then-accepted ideas about the atomic nucleus that it was never seriously discussed," fellow chemist Otto Hahn would later comment in his autobiography. In 1939, after much research had been done by many scientists, Hahn, Fritz Strassmann and Lise Meitner discovered that Noddack had been right. They named the process nuclear fission .

The Noddacks moved from Berlin to the University of Freiburg in 1935, to the University of Strasbourg in 1943, and to the State Research Institute for Geochemistry in Bamberg in 1956. In 1960, Walter Noddack died. Ida Noddack received the High Service Cross of the German Federal Republic in 1966. During her life she received honorary membership in the Spanish Society of Physics and Chemistry and the International Society of Nutrition Research, as well as an honorary doctorate of science from the University of Hamburg. Ida Noddack retired in 1968 and moved to Bad Neuenahr, a small town on the Rhine. She died in 1979.