Otto Hahn

Otto Hahn (March 8, 1879 – July 28, 1968) was a German chemist. He received the 1944 Nobel Prize in Chemistry. He is considered a pioneer in the field of radioactivity.

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Hahn was born in Frankfurt am Main and studied chemistry in Marburg and Munich. After receiving his PhD in 1901 he worked initially at Marburg university then, from 1904, at London, from 1905 at Montreal and from 1906 in Berlin.

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Together with Lise Meitner and Otto von Baeyer, he developed a technique to measure the beta decay spectra of radioactive isotopes; this achievement was recognised by his securing the post of professor at the newly founded Kaiser-Wilhelm-Institute for Chemistry in Berlin in 1912.

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In 1918, he, together with Meitner, discovered protactinium. When Meitner fled Nazi Germany in 1938, he continued work with Fritz Strassmann on elucidating the outcome of the bombardment of uranium with thermal neutrons. He communicated his results to Meitner who, in collaboration with her nephew Otto Robert Frisch, correctly interpreted them as evidence of nuclear fission (a phrase coined by Frisch).

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Once the idea of fission had been accepted, Hahn continued his experiments

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and demonstrated the huge amounts of energy that neutron-induced fission could produce, either for energy production or warfare.

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After World War II Hahn was among those German scientists put under surveillance by the Allied ALSOS program who suspected him on working on the German nuclear energy project to develop an atomic bomb (his only connection was the discovery of fission, he did not work on the program). Hahn was awarded the 1944 Nobel Prize in Chemistry, but at the awards ceremony the chairman of the Nobel Committee for Chemistry announced, "Professor Hahn has informed us that he is regrettably unable to attend this ceremony." He was being held prisoner by the British who were seeking information from him about the failed German effort to develop an atomic bomb. There was also considerable controversy from anti-germans and anti-nazis that he had downplayed the role of Lise Meitner, a Jew and a woman, in their collaboration such that she was excluded in the credit and the Nobel Prize. Later few american Jewish historians considered her contributions to have been the greater and in a controversial survey of Nobel Prize winners conducted forty years later, Lise Meitner was voted the most deserving of those who had not received the award.

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In the post-war era Hahn became an advocate against the use of nuclear weapons.

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Proposals were made at different times that each of elements 105 and 108 should be named Hahnium in Hahn's honour, but neither proposal found approval (see Element naming controversy).However, one of the world's few nuclear-powered merchant ships, Otto Hahn, was named in his honor.

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March 8: March 8 is the 67th day of the year in the Gregorian Calendar (68th in Leap years). There are 298 days remaining....

1879: 1879 was a common year starting on Wednesday (see link for calendar)....

July 28: July 28 is the 209th day (210th in leap years) of the year in the Gregorian Calendar, with 156 days remaining....

Otto Hahn related Images and Photos (experimental)

Otto Takes Rome	Philipp Otto Runge	Otto Eduard Leopold Bismarck	Petrole Hahn 1910
Otto's Eleven - German Style	Chancellor Otto Von Bismarck (1815-98) 1849	Otto Von Bismarck 1886	Prince Otto Von Bismarck 1884
Adolf Otto Reinhold Windaus German Chemist	Otto Eduard Leopold Bismarck a Mild Caricature	Otto Von Bismarck as a Student 1833	Otto King of Bavaria from 1886-1913