# Arthur Amos Noyes

"Arthur Noyes" redirects here. For articles related to Arthur H. Noyes, an early 20th-century judge of the United States territorial court based in Alaska, see Nome Gold Rush and The Spoilers (Beach novel).
Arthur Amos Noyes
Born September 13, 1866
Newburyport, Massachusetts, USA
Died June 3, 1936 (aged 69)
California, USA
Nationality United States
Fields Chemistry
Institutions MIT
Caltech
Alma mater MIT
University of Leipzig
Doctoral students Roscoe G. Dickinson
Known for Electrolytes
Notable awards Gibbs Medal (1915)
Davy Medal (1927)

Arthur Amos Noyes (September 13, 1866 – June 3, 1936) was a U.S. chemist and educator. He served as the acting president of MIT between 1907 and 1909. He received a PhD. in 1890 at Leipzig under the guidance of Wilhelm Ostwald. Roscoe Gilkey Dickinson was one of his famous students. Noyes served as Professor of Chemistry at the California Institute of Technology from 1919 to 1936. He was a major influence on the educational philosophy and the core curriculum of Caltech. He also served on the board of trustees for Science Service, now known as Society for Science & the Public, between 1921 and 1927.

## Noyes–Whitney equation

Along with Willis Rodney Whitney, he formulated the Noyes–Whitney equation in 1897, which relates the rate of dissolution of solids to the properties of the solid and the dissolution medium. It is an important equation in pharmaceutical science. The relation is given by:

${\displaystyle {\frac {dW}{dt}}={\frac {DA(C_{s}-C)}{L}}}$

Where:

• ${\displaystyle {\frac {dW}{dt}}}$ is the rate of dissolution.
• A is the surface area of the solid.
• C is the concentration of the solid in the bulk dissolution medium.
• ${\displaystyle C_{s}}$ is the concentration of the solid in the diffusion layer surrounding the solid.
• D is the diffusion coefficient.
• L is the diffusion layer thickness.

## References

• "Arthur Amos Noyes: Sept. 13, 1866 – June 3, 1936 (A biographical memoir)," in Biographical Memoirs, Vol. 31, Columbia University Press (For the National Academy of Sciences of the United States), New York, 1958, pp. 322–346.
• Dictionary of Scientific Biography, Charles Scribner's Sons, 1970–1990, vol. 10, pp. 156–157.
• Biog. Mem. Nat. Acad. Sci., 1958, 31, pp. 322–346.
• Proc. Welch Fdn. Conf. 1977, 20, pp. 88–105.
• Science 1936, 83, pp. 613–614.
• Science 1936, 84, pp. 217–220.
• Sci. Monthly 1936, 43, pp. 179–181.
• Ind. Eng. Chem. 1931, 23, pp. 443–445.
• American Chemists and Chemical Engineers, Ed. W.D. Miles, American Chemical Society, 1976, pp. 371–372.
• Proc. Am. Acad. Arts Sci. 1940, 74, pp. 150–155.