Childhood & Early Life
Frederick Soddy was born on 2 September 1877 in Eastbourne, a seaside resort in Sussex, England. His father, Benjamin Soddy, was a corn merchant in London. Frederick was the youngest of his father’s seven children. His mother died when he was two years old and he was raised by a half sister.
Young Soddy had his schooling at Eastbourne College. Later he got admitted to University College of Wales at Aberystwyth. In 1895, he received a scholarship and shifted to Merton College, Oxford; ultimately passing out from there in 1898 with first class honors in chemistry.
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In 1898, Frederick Soddy began his career as an independent researcher at Oxford. In 1900, he shifted to Canada and there he became a demonstrator in chemistry at McGill University in Montreal. Soon, he came in contact with Ernest Rutherford, who asked him to identify the thorium emanations.
Soddy and Rutherford worked together for two years on thorium and discovered a highly radioactive substance called thorium-X. They then kept on experimenting on different radioactive elements and finally in 1902, established the ‘Theory of Atomic Disintegration’.
They proposed that radioactivity was an atomic phenomenon and that radioactive emission occurs when chemical transmutations of the atoms take place. Later they demonstrated that radioactive elements behave anomalously because they have a propensity to decay and form other elements.
They also noted that such decay produces alpha, beta and gama radiation. Moreover, they also noticed gaseous emanation from thorium, but could only conclude that it was an inert gas.
Subsequently, Soddy went back to England to work with Sir William Ramsay at University College London. That was mainly because Ramsay’s laboratory was at that time the only place where he could successfully examine minute amount of rare gases.
Here he continued to study radium emanation and in July 1903, showed experimentally that helium is produced when radium bromide is decayed radioactively. He also concluded that the gas originated in the alpha particles. Thus he guessed that they were helium nuclei.
In 1904, Soddy was appointed as a lecturer in physical chemistry and radioactivity in the University of Glasgow. He immediately started experimenting in the later field. The first few years were spent in purifying radioactive materials.
In 1910, he turned his attention to short lived radio elements. In this, he collaborated with Alexander Fleck and established that in many cases a number of intermediates were not only chemically same, but was also inseparable; yet they go through radioactive decay differently.
He continued working on the puzzle and subsequently established that emission of an alpha-particle from an element causes that element to move back two places in the Periodic Table. Contrarily, beta emission causes the element to go up one place in the same table.
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In 1913, he joined the two theories to propose his ‘Displacement Law’. In the same year, he also proposed that certain elements exist in two or more forms, which might be chemically indistinguishable and inseparable, but may have different atomic weight. He called them isotopes
In 1914, Soddy shifted to the University of Aberdeen as a Professor of Chemistry. However, as the First World War broke out, he could not continue with his research as his laboratory started being used for war oriented experimentations.
In spite of such restrictions, Soddy along with John Arnold Cranston discovered the stable isotope of Protactinium. It is believed that they had actually discovered it in 1915, but could publish the paper only in 1918 as Cranston was drafted into military service and the note remained locked up in his laboratory.
In 1919, Soddy joined the University of Oxford as Lee’s Professor of Inorganic and Physical Chemistry; a position he held until his retirement in 1937. Although he reorganized the chemistry syllabus and the laboratories, he did little personal research.
He now began to show more interest in economic, social and political dilemmas as well as in different mathematical and economical problems. At the same time, he continued with his writing works. His ‘Interpretation of the Atom’ was published in 1932.
Frederick Soddy is best remembered for his discovery of isotopes. The underlying concept of this discovery is that different elements with different atomic weight but identical chemical characteristics might be assigned to the same chemical space. He later named these elements isotopes, which in Greek means ‘the same place’, on the advice of family friend Dr. Margaret Todd.
In addition, Soddy had number of books to his credit. Apart from the above mentioned ‘The Interpretation of the Atom’, some of his more important works are 'Radioactivity’, ‘The Interpretation of Radium’, ‘The Chemistry of the Radioactive Elements’, ‘Matter and Energy’, ‘Science and Life’, ‘The Story of Atomic Energy’, and ‘Atomic Transmutation’.
Personal Life & Legacy
In 1908, Soddy married Winifred Beilby, the daughter of renowned Chemist, Sir George Beilby. The couple did not have any children. If hearsays are to be believed it was Winifred’s death that led to his disenchantment with experimental science and he retired prematurely. He died on September 22, 1956 at Brighton.
A small crater on the moon has been named after Fredrick Soddy. Soddyite, a radioactive Uranium mineral, also bears his name.