Theodore William Richards
Born: 31 January 1868, Germantown, PA, USA
Died: 2 April 1928, Cambridge, MA, USA
Affiliation at the time of the award: Harvard University, Cambridge, MA, USA
Prize motivation: "in recognition of his accurate determinations of the atomic weight of a large number of chemical elements."
Prize share: 1/1
The world around us consists of molecules that are composed of atoms. There are a number of different types of atoms, which are called elements. The atoms for different elements have different masses. Determining atomic masses is important in calculating the relative quantification among substances in chemical reactions. Theodore Richards developed methods for very precise determination of atomic masses. As a result of these methods, sources of errors, including moisture in tests, were reduced. Around 1904 Theodore Richards was able to correct previous values for a number of different atomic masses.