Jean Stas

Jean Servais Stas ( born August 21, 1813 in Leuven, at the time France, † December 13, 1891 in Brussels, Belgium) was a Belgian chemist. He led for the first time by exact measurements of atomic mass, including the carbon.

Life and work

Stas was by training physicians. In 1837 he went to Paris at the Ecole polytechnique to work as assistant to the French chemist Jean Baptiste Dumas. Between 1840 and 1869 Stas was a professor at the Ecole Royale Militaire in Brussels. He advised the Belgian government in military matters.

During this time, Stas demonstrated for the first time that nicotine was used in a murder as a poison, which the case of the murdered by Hippolyte de Visart Bocarmé Gustave Fougnies entered the criminal history. His writing " Forensic studies on the nicotine " is an early work of modern toxicology. His analytical work form the basis for the named after him and the German chemist Friedrich Julius Otto Stas -Otto - separation process in pharmaceutical analysis.

During his time in Paris as an assistant to Dumas ' he led from measurements of atomic masses - including the first time the exact atomic mass of carbon - which he specified later and spread to many chemical elements. Meanwhile he took the oxygen = 16 as a reference point. His measurements did not confirm the long believed hypothesis of the English physician William Prout, that the atomic masses would have to be integers. His work laid the foundation for the work of Dmitri Mendeleev and others on the periodic table of elements. For over 50 years remained the measurements Stas ' standard.

Stas had to retire in 1869 because of problems with his voice, but was shortly thereafter used as a Commissioner of the Belgian coin. From this position he joined in 1872 because of differences over monetary policy of his country back.

Jean Servais Stas died on 13 December 1891 in Brussels.

Jean -Servais Stas - Medal of GTFCh

The scientific society founded in 1978, Society of Toxicological and Forensic Chemistry ( GTFCh ), headquartered in Frankfurt am Main, has been giving 1979 as a year, since 1989 every second year an award for " contributions to the forensic sciences." In honor of Jean Servais Stas this award was named after him as Jean -Servais Stas - Medal.