François-Marie Raoult

François Marie Raoult ( born May 10, 1830 in Fournes -en- Weppes, Nord, † April 1, 1901 in Grenoble ) was a French physicist and chemist.

After a stay at the school of Reims in 1853, and various intermediate positions, he became in 1862 the lycee professor of chemistry in Sens, where he wrote a thesis on the electromotive force, for which he received a doctorate in Paris the following year. In 1867 he was responsible for the chemistry classes in Grenoble and three years later he was appointed Professor of Chemistry, he innebehielt until his death on April 1, 1901. Raoult's earliest researches were occupied physical issues, especially with the phenomena of the galvanic cell. Later he devoted himself more purely chemical questions. His name is best known in connection with the work on solutions to which he devoted the last two decades of his life. His first work dealt with the lowering of the freezing point of liquids by the presence of other substances. Further studies and experiments with different solvents in addition to water, such as benzene, and acetic acid led him to a simple relationship between the molecular weight of the agents and the freezing point of the solvent, and that when a molecule of a substance can be dissolved in a molecule of any solvent, the temperature of the freezing the latter was lowered by 0.63 ° C. Another context in which he was working, was the reduction of the vapor pressure of a solvent, by dissolving a substance which is proportional to the molar mass of the solute, at least when it dilutes the solution. These two generalizations not only provided a new method for determination of the molar mass of substances, but were also of Jacobus Henricus van ' t Hoff, Wilhelm Ostwald and other chemist, used to support the hypothesis of electrolytic dissociation in solutions. Named after him Raoult's law describes the vapor pressure of ideal mixtures.

Honors

• Prix ​​International de Chimie Lacaze (1889 )
• Davy Medal ( 1892)
• Prix ​​de l'Institut (1895 )
• Commandeur de la Légion d' Honneur (1900)