Theodore William Richards

Theodore William Richards
Born	January 31, 1868 Germantown, Pennsylvania, America
Died	April 2 1928 Cambridge, Massachusetts
Residence	United States,
Nationality	American
Fields	Physical chemistry
Institutions	Harvard University
Alma mater	Haverford College Harvard University
Doctoral advisor	Josiah Parsons Cooke
Known for	Atomic weights Thermochemistry Electrochemistry
Notable awards	Nobel Prize for Chemistry (1914)

Theodore William Richards (January 31, 1868 – April 2, 1928) was the first American scientist to receive the Nobel Prize in Chemistry, earning the award "in recognition of his exact determinations of the atomic weights of a large number of the chemical elements."[1]

Education and personal life

Theodore Richards was born in Germantown, Pennsylvania to William Trost Richards, a land- and seascape painter, and Anna née Matlack, a poet. Richards received most of his pre-college education from his mother. During one summer's stay at Newport, Rhode Island, Richards met Professor Josiah Parsons Cooke of Harvard, who showed the young boy Saturn's rings through a small telescope. Years later Cooke and Richards would work together in Cooke's laboratory.

Beginning in 1878, the Richards family spent two years in Europe, largely in England, where Theodore Richards' scientific interests grew stronger. After the family's return to the United States, he entered Haverford College, Pennsylvania in 1883 at the age of 14, earning a Bachelor of Science degree in 1885. He then enrolled at Harvard University and received a Bachelor of Arts degree in 1886, as further preparation for graduate studies.

Richards continued on at Harvard, obtaining a Ph.D. in chemistry in 1888 for a determination of the atomic weight of oxygen relative to hydrogen. His doctoral advisor was Josiah Parsons Cooke. Following a year of post-doctoral work in Germany, where he studied under Victor Meyer and others, Richards returned to Harvard as an assistant in chemistry, then instructor, assistant professor, and finally full professor in 1901. In 1903 he became chairman of the Department of Chemistry at Harvard, and in 1912 he was appointed Erving Professor of Chemistry and Director of the new Wolcott Gibbs Memorial Laboratory.

In 1896, Richards married Miriam Stuart Thayer in 1896. The couple had one daughter, Grace Thayer (who married James Bryant Conant), and two sons, Greenough Thayer and William Theodore. Both sons died by suicide.[2]

Richards' maintained interests in both art and music. Among his recreations were sketching, golf, and sailing. He died at Cambridge, Massachusetts, on April 2, 1928, at the age of 60.

Scientific work

About half of Richard's scientific research concerned atomic weights, starting in 1886 with his graduate studies. On returning to Harvard in 1889, this was his first line of research, continuing up to his death. According to Forbes, by 1932 the atomic weights of 55 elements had been studied by Richards and his students.[3] Among the potential sources of error Richards uncovered in such determinations was the tendency of certain salts to occlude gases or foreign solutes on precipitation.[4]

Richards was the first to show, by chemical analysis, that an element could have different atomic weights. He was asked to analyze samples of naturally-occurring lead and lead produced by radioactive decay. His measurements showed that the two samples had different atomic weights, supporting the concepts of isotopes.[5][6]

Although Richards' chemical determinations of atomic weights were highly significant for their time, they have largely been superseded. Modern scientists use electronic instrumentation, such as mass spectrometers, to determine both the masses and the abundances of an element's isotopes. From this information, an average atomic mass can be calculated, and compared to the values measured by Richards. The modern methods are faster and more sensitive than those on which Richards had to rely, but not necessarily less expensive.

Other scientific work of Theodore Richards included investigations of the compressibilities of atoms, heats of solution and neutralization, and the electrochemistry of amalgams. His investigation of electrochemical potentials at low temperatures was among the work that led, in the hands of others, to the Nernst heat theorem and the third law of thermodynamics, although not without heated debate between Nernst and Richards.[7]

Richards also is credited with the invention of the adiabatic calorimeter as well as the nephelometer, which was devised for his work on the atomic weight of strontium.

Graph of periodic properties by Richards, Journal of the American Chemical Society, volume 37, issue 7 ,1915

Selected writings

* Richards, Theodore W. (1915). "Concerning the Compressibilities of the Elements, and Their Relations to Other Properties". Journal of the American Chemical Society 37 (7): 1643 – 1656.

* Richards, Theodore W.; Forbes, George Shannon (1906). "Energy Changes Involved in the Dilution of Zinc and Cadmium Amalgams". Carnegie Institution Report: 1 – 68.

* Richards, Theodore W. (1913). The Scientific Work of Morris Loeb. Harvard University Press.

Activities and honors

* Lowell Lectures (1908)

* Davy Medal (1910)

* Faraday Medal (1911)

* Willard Gibbs Medal (1912)

* President of the American Chemical Society (1914)

* Nobel Prize in Chemistry (1914)

* Franklin Medal (1916)

* President of the American Association for the Advancement of Science (1917)

* President of the American Academy of Arts and Sciences President (1919 – 1921)

* Lavoisier Medal (1922)

* Le Blanc Medal (1922)

* Theodore Richards Medal (1932, awarded posthumously)

See also

* Mass spectrometry

* Jöns Jakob Berzelius

* Farrington Daniels

* Gilbert Newton Lewis

* Jean Stas

References and notes

1. ^ Nobel Prize in Chemistry 1914 - Presentation. Retrieved on 2007-12-24.

2. ^ Conant, Jennet (2002). Tuxedo Park. Simon & Schuster. - See pages 1 – 3 for William Theodore Richards and page 126 for Greenough Thayer Richards.

3. ^ Forbes, George Shannon (1932). "Investigations of Atomic Weights by Theodore William Richards". Journal of Chemical Education 9: 453 – 458.

4. ^ Hartley, Harold (August 1930). "Theodore William Richards Memorial Lecture". Journal of the Chemical Society: 1945.

5. ^ Kopperl, Sheldon J. (1983). "Theodore W. Richards: America's First Nobel Laureate in Chemistry". Journal of Chemical Education 60: 738 – 739.

6. ^ Harrow, Benjamin (1920). Eminent Chemists of Our Time. Van Nostrand, 74.

7. ^ Nernst, Walther (1926). The New Heat Theorem. Methuen and Company, Ltd. - Reprinted in 1969 by Dover - See especially pages 227 – 231 for Nernst's comments on Richards work

8. ^ Richards, Theodore W. (1915). "Concerning the Compressibilities of the Elements, and Their Relations to Other Properties". Journal of the American Chemical Society 37 (7): 1643 – 1656.

Further reading