Frederick Soddy

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Frederick Soddy
Frederick Soddy.jpg
Born(1877-09-02)2 September 1877
Died22 September 1956(1956-09-22) (aged 79)
Brighton, Sussex, England
Nationality British
Alma mater
Known for
Spouse(s)Winifred Beilby [1]
Scientific career

Frederick Soddy FRS [2] (2 September 1877 – 22 September 1956) was an English radiochemist who explained, with Ernest Rutherford, that radioactivity is due to the transmutation of elements, now known to involve nuclear reactions. He also proved the existence of isotopes of certain radioactive elements. [3] [4] [5] [6] [7] [8] [9] [10]

Royal Society English learned society for science

The President, Council and Fellows of the Royal Society of London for Improving Natural Knowledge, commonly known as the Royal Society, is a learned society. Founded on 28 November 1660, it was granted a royal charter by King Charles II as "The Royal Society". It is the oldest national scientific institution in the world. The society is the United Kingdom's and Commonwealth of Nations' Academy of Sciences and fulfils a number of roles: promoting science and its benefits, recognising excellence in science, supporting outstanding science, providing scientific advice for policy, fostering international and global co-operation, education and public engagement.

England Country in north-west Europe, part of the United Kingdom

England is a country that is part of the United Kingdom. It shares land borders with Wales to the west and Scotland to the north-northwest. The Irish Sea lies west of England and the Celtic Sea lies to the southwest. England is separated from continental Europe by the North Sea to the east and the English Channel to the south. The country covers five-eighths of the island of Great Britain, which lies in the North Atlantic, and includes over 100 smaller islands, such as the Isles of Scilly and the Isle of Wight.

Radiochemistry is the chemistry of radioactive materials, where radioactive isotopes of elements are used to study the properties and chemical reactions of non-radioactive isotopes. Much of radiochemistry deals with the use of radioactivity to study ordinary chemical reactions. This is very different from radiation chemistry where the radiation levels are kept too low to influence the chemistry.



Soddy was born at 5 Bolton Road, Eastbourne, England, the son of Benjamin Soddy, corn merchant, and his wife Hannah Green. He went to school at Eastbourne College, before going on to study at University College of Wales at Aberystwyth and at Merton College, Oxford, where he graduated in 1898 with first class honors in chemistry. [1] He was a researcher at Oxford from 1898 to 1900.

Eastbourne Town and Borough in England

Eastbourne is a town, seaside resort and borough in the non-metropolitan county of East Sussex on the south coast of England, 19 miles (31 km) east of Brighton. Eastbourne is immediately to the east of Beachy Head, the highest chalk sea cliff in Great Britain and part of the larger Eastbourne Downland Estate.

Eastbourne College

Eastbourne College is a British co-educational independent school for day and boarding pupils aged 13–18, in the town of Eastbourne on the south coast of England. The College's headmaster is Tom Lawson.

Aberystwyth University university in Wales

Aberystwyth University is a public research university in Aberystwyth, Wales. Aberystwyth was a founding member institution of the former federal University of Wales. The university has almost 8,000 students studying across 3 academic faculties and 17 departments.

Scientific career

In 1900 he became a demonstrator in chemistry at McGill University in Montreal, Quebec, where he worked with Ernest Rutherford on radioactivity. [11] [1] He and Rutherford realized that the anomalous behaviour of radioactive elements was because they decayed into other elements. This decay also produced alpha, beta, and gamma radiation. When radioactivity was first discovered, no one was sure what the cause was. It needed careful work by Soddy and Rutherford to prove that atomic transmutation was in fact occurring.

Chemistry is the scientific discipline involved with elements and compounds composed of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during a reaction with other substances.

McGill University English-language university in Montreal, Quebec

McGill University is a public research university in Montreal, Quebec, Canada. It was established in 1821 by royal charter, granted by King George IV. The university bears the name of James McGill, a Montreal merchant originally from Scotland whose bequest in 1813 formed the university's precursor, McGill College.

Montreal City in Quebec, Canada

Montreal is the most populous municipality in the Canadian province of Quebec and the second-most populous municipality in Canada. Originally called Ville-Marie, or "City of Mary", it is named after Mount Royal, the triple-peaked hill in the heart of the city. The city is centred on the Island of Montreal, which took its name from the same source as the city, and a few much smaller peripheral islands, the largest of which is Île Bizard. It has a distinct four-season continental climate with warm to hot summers and cold, snowy winters.

In 1903, with Sir William Ramsay at University College London, Soddy showed that the decay of radium produced helium gas. [1] In the experiment a sample of radium was enclosed in a thin-walled glass envelope sited within an evacuated glass bulb. After leaving the experiment running for a long period of time, a spectral analysis of the contents of the former evacuated space revealed the presence of helium. [12] Later in 1907, Rutherford and Thomas Royds showed that the helium was first formed as positively charged nuclei of helium (He2+) which were identical to alpha particles, which could pass through the thin glass wall but were contained within the surrounding glass envelope. [13]

William Ramsay Scottish chemist (1852–1916)

Sir William Ramsay, was a Scottish chemist who discovered the noble gases and received the Nobel Prize in Chemistry in 1904 "in recognition of his services in the discovery of the inert gaseous elements in air". After the two men identified argon, Ramsay investigated other atmospheric gases. His work in isolating argon, helium, neon, krypton and xenon led to the development of a new section of the periodic table.

University College London, which has operated under the official name of UCL since 2005, is a public research university located in London, United Kingdom. It is a constituent college of the federal University of London, and is the third largest university in the United Kingdom by total enrolment, and the largest by postgraduate enrolment.

Radium Chemical element with atomic number 88

Radium is a chemical element with symbol Ra and atomic number 88. It is the sixth element in group 2 of the periodic table, also known as the alkaline earth metals. Pure radium is silvery-white, but it readily reacts with nitrogen (rather than oxygen) on exposure to air, forming a black surface layer of radium nitride (Ra3N2). All isotopes of radium are highly radioactive, with the most stable isotope being radium-226, which has a half-life of 1600 years and decays into radon gas (specifically the isotope radon-222). When radium decays, ionizing radiation is a product, which can excite fluorescent chemicals and cause radioluminescence.

From 1904 to 1914, Soddy was a lecturer at the University of Glasgow. In May 1910 Soddy was elected a Fellow of the Royal Society. [2] [14] In 1914 he was appointed to a chair at the University of Aberdeen, where he worked on research related to World War I.

University of Glasgow University located in Glasgow, Scotland and founded in 1451.

The University of Glasgow is a public research university in Glasgow, Scotland. Founded by papal bull in 1451, it is the fourth-oldest university in the English-speaking world and one of Scotland's four ancient universities. Along with the universities of Edinburgh, Aberdeen, and St. Andrews, the university was part of the Scottish Enlightenment during the 18th century.

Fellow of the Royal Society Elected Fellow of the Royal Society, including Honorary, Foreign and Royal Fellows

Fellowship of the Royal Society is an award granted to individuals that the Royal Society of London judges to have made a 'substantial contribution to the improvement of natural knowledge, including mathematics, engineering science and medical science'.

University of Aberdeen university in Aberdeen, Scotland

The University of Aberdeen is a public research university in Aberdeen, Scotland. It is an ancient university founded in 1495 when William Elphinstone, Bishop of Aberdeen and Chancellor of Scotland, petitioned Pope Alexander VI on behalf of James IV, King of Scots to establish King's College, making it Scotland's third-oldest university and the fifth-oldest in the English-speaking world. Today, Aberdeen is consistently ranked among the top 200 universities in the world and is ranked within the top 30 universities in the United Kingdom. Aberdeen was also named the 2019 Scottish University of the Year by The Times and Sunday Times Good University Guide.

The work that Soddy and his research assistant Ada Hitchins did at Glasgow and Aberdeen showed that uranium decays to radium. [15] It also showed that a radioactive element may have more than one atomic mass though the chemical properties are identical. [16] Soddy named this concept isotope meaning 'same place'. The word 'isotope' was initially suggested to him by Margaret Todd. Later, J. J. Thomson showed that non-radioactive elements can also have multiple isotopes.

Ada Florence Remfry Hitchins was the principal research assistant of British chemist Frederick Soddy, who won the Nobel prize in 1921 for work on radioactive elements and the theory of isotopes. Hitchins isolated samples from uranium ores, taking precise and accurate measurements of atomic mass that provided the first experimental evidence for the existence of different isotopes. She also helped to discover the element protactinium, which Dmitri Mendeleev had predicted should occur in the periodic table between uranium and thorium.

Uranium Chemical element with atomic number 92

Uranium is a chemical element with symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weakly radioactive because all isotopes of uranium are unstable, with half-lives varying between 159,200 years and 4.5 billion years. The most common isotopes in natural uranium are uranium-238 and uranium-235. Uranium has the highest atomic weight of the primordially occurring elements. Its density is about 70% higher than that of lead, and slightly lower than that of gold or tungsten. It occurs naturally in low concentrations of a few parts per million in soil, rock and water, and is commercially extracted from uranium-bearing minerals such as uraninite.

Atomic mass mass of an atom in unified atomic mass units

The atomic mass (ma) is the mass of an atom. Its unit is the unified atomic mass units where 1 unified atomic mass unit is defined as ​112 of the mass of a single carbon-12 atom, at rest. For atoms, the protons and neutrons of the nucleus account for nearly all of the total mass, and the atomic mass measured in u has nearly the same value as the mass number.

In 1913, Soddy also showed that an atom moves lower in atomic number by two places on alpha emission, higher by one place on beta emission. This was discovered at about the same time by Kazimierz Fajans, and is known as the radioactive displacement law of Fajans and Soddy, a fundamental step toward understanding the relationships among families of radioactive elements. Soddy published The Interpretation of Radium (1909) and Atomic Transmutation (1953).

In 1918 he announced discovery of a stable isotope of Protactinium, working with John Arnold Cranston. This slightly post-dated its discovery by German counterparts; however, it is said their discovery was actually made in 1915 but its announcement was delayed due to Cranston's notes being locked away whilst on active service in the First World War. [17]

In 1919 he moved to the University of Oxford as Dr Lee's Professor of Chemistry, where, in the period up till 1936, he reorganized the laboratories and the syllabus in chemistry. He received the 1921 Nobel Prize in chemistry for his research in radioactive decay and particularly for his formulation of the theory of isotopes.

His work and essays popularising the new understanding of radioactivity was the main inspiration for H. G. Wells's The World Set Free (1914), which features atomic bombs dropped from biplanes in a war set many years in the future. Wells's novel is also known as The Last War and imagines a peaceful world emerging from the chaos. In Wealth, Virtual Wealth and Debt Soddy praises Wells’s The World Set Free. He also says that radioactive processes probably power the stars.


In four books written from 1921 to 1934, Soddy carried on a "campaign for a radical restructuring of global monetary relationships", [18] offering a perspective on economics rooted in physics – the laws of thermodynamics, in particular – and was "roundly dismissed as a crank". [18] While most of his proposals – "to abandon the gold standard, let international exchange rates float, use federal surpluses and deficits as macroeconomic policy tools that could counter cyclical trends, and establish bureaus of economic statistics (including a consumer price index) in order to facilitate this effort" – are now conventional practice, his critique of fractional-reserve banking still "remains outside the bounds of conventional wisdom" although a recent paper by the IMF reinvigorated his proposals. [18] [19] Soddy wrote that financial debts grew exponentially at compound interest but the real economy was based on exhaustible stocks of fossil fuels. Energy obtained from the fossil fuels could not be used again. This criticism of economic growth is echoed by his intellectual heirs in the now emergent field of ecological economics. [18]

Antisemitic views

In Wealth, Virtual Wealth and Debt Soddy cited the (fraudulent) Protocols of the Learned Elders of Zion as evidence for the belief, which was relatively widespread at the time, of a "financial conspiracy to enslave the world". He used the imagery of a Jewish conspiracy to buttress his claim that "A corrupt monetary system strikes at the very life of the nation." In the same document, he made reference to "the semi-Oriental" who is "supreme" in "high finance" and to an "iridescent bubble of beliefs blown around the world by the Hebraic hierarchy". Later in life he published a pamphlet Abolish Private Money, or Drown in Debt (1939) with a noted publisher of anti-Semitic texts. [20] The influence of his writing can be gauged, for example, in this quote from Ezra Pound:

"Professor Frederick Soddy states that the Gold Standard monetary system has wrecked a scientific age! ... The world's bankers ... have not been content to take their share of modern wealth production – great as it has been – but they have refused to allow the masses of mankind to receive theirs." [21]

Descartes' theorem

He rediscovered the Descartes' theorem in 1936 and published it as a poem, "The Kiss Precise", quoted at Problem of Apollonius. The kissing circles in this problem are sometimes known as Soddy circles.

Honours and awards

He received the Nobel Prize in Chemistry in 1921 and the same year he was elected member of the International Atomic Weights Committee. A small crater on the far side of the Moon as well as the radioactive Uranium mineral Soddyite are named after him. [22]

Personal life

Soddy married Winifred Beilby, the daughter of Sir George Beilby, in 1908. He died in Brighton, England in 1956. [1]


See also

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  7. Sclove, R. E. (1989). "From Alchemy to Atomic War: Frederick Soddy's "Technology Assessment" of Atomic Energy, 1900–1915". Science, Technology & Human Values. 14 (2): 163–194. doi:10.1177/016224398901400203., pp. 163–194
  8. Linda Merricks (1996). The World Made New: Frederick Soddy, Science, Politics, and Environment. Oxford New York: Oxford University Press. p. 223. ISBN   0-19-855934-8.
  9. A. N. Krivomazov (1978). Frederick Soddy: 1877–1956. Moscow: Nauka. p. 208.
  10. George B. Kauffman (1986). Frederick Soddy (1877–1956): Early Pioneer in Radiochemistry (Chemists and Chemistry). Dordrecht; Boston; Hingham: D. Reidel Pub. Co. p. 272. ISBN   978-90-277-1926-3.
  11. John Gribbin (2014). 13.8: The Quest to Find the True Age of the Universe and the Theory of Everything. London: Icon Books. ISBN   978-1-84831-918-9.
  12. William Ramsay, Frederick Soddy (1903). "Experiments in Radioactivity, and the Production of Helium from Radium". Proceedings of the Royal Society of London.72.204 – 207
  13. "Library and Archive". Royal Society. Retrieved 19 October 2010.
  14. Soddy, Frederick; Hitchins, A. F. R. (August 1915). "XVII. The relation between uranium and radium.—Part VI. The life-period of ionium". Philosophical Magazine. 6. 30 (176): 209–219. doi:10.1080/14786440808635387.
  15. Soddy, Frederick (15 February 1917). "The Atomic Weight of "Thorium" Lead". Nature. 98 (2468): 469–469. Bibcode:1917Natur..98Q.469S. doi:10.1038/098469a0 . Retrieved 12 April 2014.
  17. 1 2 3 4 Zencey, Eric (12 April 2009). "Mr. Soddy's Ecological Economy" (Opinion). The New York Times. Retrieved 22 December 2017.
  18. Beneš, Jaromír; Kumhof, Michael. "The Chicago Plan Revisited". SSRN   2169748 .Missing or empty |url= (help)
  19. Frederick Soddy's Economics and the Protocols of the Elders of Zion (1939)
  20. Surette, Leon (1999). Pound in Purgatory: From Economic Radicalism to Anti-Semitism. University of Illinois Press. p. 218.
  21. Soddyite Mineral Data