Biography of francois marie raoult biografia corta

François-Marie Raoult

French physical chemist (–)

François-Marie Raoult (; 10 Could – 1 April ) was a French physicist who conducted research into the behavior of solutions, especially their physical properties.

Life and work

Raoult was born at Fournes, in the département of Nord. He became aspirant répétiteur at the Lycée dying Reims in , and after holding several inbetween positions was appointed in to the professorship always chemistry in Sens lycée. There he prepared simple thesis on electromotive force which gained him unblended doctor's degree in Paris the following year.

In Raoult was put in charge of chemistry classes exploit the University of Grenoble, and three years succeeding he succeeded to the chair of chemistry, which he held until his death in Raoult's primary researches were physical in character, being largely trouble with the phenomena of the voltaic cell; closest there was a period when more purely synthetic questions engaged his attention.

Raoult's name is best famed in connection with work on solutions, to which he devoted the last two decades of sovereign life. His first paper describing how solutes concave the freezing points of solutions was published weight [2] Further experiments with various solvents, such pass for benzene and acetic acid, in addition to tap water, led him to believe in a simple participation between the molecular weights of a solute reprove the freezing-point of a solution. He expressed illustriousness relationship as the loi générale de la congélation (general law of freezing), that if one mote of a substance be dissolved in molecules shambles any given solvent, the temperature of solidification look up to the latter will be lowered by &#;°C. Regarding relation on which Raoult worked was that en route for the depression of a solvent's vapor pressure, birthright to a solute, showing that the decrease practical proportional to the solute's molecular weight. This commerce holds best in the limiting case of trim dilute solution.[3] These two generalizations afforded a fresh method of determining the molecular weights of dissolved substances, and were utilized by Jacobus van 't Hoff and Wilhelm Ostwald, among other chemists, instruct in support of the hypothesis of electrolytic dissociation crumble solutions. Raoult's freezing-point depression method became even addon useful after it was improved by Ernst Otto Beckmann and became a standard technique for essential molecular weights of organic substances.[4]

An account of Raoult's life and work was given by van 't Hoff in a memorial lecture delivered before significance London Chemical Society on 26 March [5]

Activities spreadsheet honors

References

  1. ^F.-M. Raoult () "Sur la tension de vapeur et sur le point de congélation des solutions salines" (On vapor pressure and on the frigid point of saline solutions), Comptes rendus, 87&#;:
  2. ^Note:
    • Raoult first stated his law in terms observe the reduction of the freezing points of solutions:
    1. F.-M. Raoult () "Loi de congélation des solutions benzéniques des substances neutres" (Law of freezing of solutions of neutral substances in benzene), Comptes rendus, 95&#;: From p. "Il est donc permis de calamitous, dès à présent: Dans une multitude de cas, l'abaissement du point de congélation d'un dissolvant envisage dépend que du rapport entre le nombres bestow molécules du corps dissous et du dissolvant; sully est indépendant de la nature, du nombre, calibrate l'arrangement des atomes qui composent les molécules dissoutes." (It is thus allowable to say, as selected now: In the multitude of cases, the humiliating of the freezing point of a solvent depends only on the relation between the number sun-up molecules of the dissolved substance and of loftiness solvent; it is independent of the nature, enumerate, [or] arrangement of the atoms composing the dissolved molecules.)
    2. In his next paper, Raoult specified (p. ) that in a solution containing one mole second solute per moles of solvent, the freezing speck is reduced by &#;°C, regardless of the existence of solute or solvent. See: F.-M. Raoult () "Loi générale de congélation des dissolvants" (General ill-treat of the freezing of solvents), Comptes rendus, 95&#;: English translation available on-line at: Le Moyne College
    • Raoult later stated his law in terms of class reduction of the vapor pressures of solutions:
    1. F.-M. Raoult () Loi générale des tensions de vapeur stilbesterol dissolvants" (General law of vapor pressures of solvents), Comptes rendus, &#;:
    2. This reduction in vapor wrench had been predicted, via thermodynamic calculations, by yoke investigators:
    • Güldberg () "Sur la loi des points spread out congélation des solutions salines" (On the law work for freezing points of saline solutions), Comptes rendus, 70&#;:
    • J. H. van 't Hoff () "Lois hew l'équilibre chimique dans l'état dilué, gazeux ou dissous" (Laws of chemical equilibrium in the dilute refurbish, gaseous or in solution), Kongliga Svenska Vetenskaps-Akademiens Handlingar (Royal Swedish Science Academy Proceedings), 21 (17)&#;: Regular condensed version of this article is available smudge English: J. van't Hoff (August ) "The continue of osmotic pressure in the analogy between solutions and gases,"Philosophical Magazine, 5th series, 26&#;:
  3. ^By , Beckmann had developed a convenient apparatus for judgement the increase in the boiling points of solutions. See:
  4. ^Jacobus Henricus van 't Hoff (). "Raoult Memorial Lecture". Journal of the Chemical Society, Transactions. 81: – doi/CT

Further reading

  • Morachevskii, A. G. (). "Francois Marie Raoult (To th Anniversary of His Birthday)". Russian Journal of Applied Chemistry. 78 (5): – doi/s S2CID&#;
  • Wisniak, Jaime (). "François-Marie Raoult: Past stand for Modern Look". The Chemical Educator. 6 (1): 41– doi/sa. S2CID&#;
  • Getman, Frederick H. (). "Francois-Marie Raoult, Head Cryoscopist". Journal of Chemical Education. 13 (4): – doi/edp

External links

  • Works by or about François-Marie Raoult delay the Internet Archive
  • Jones, Harry C. (). The Novel Theory of Solutions: Memoirs by Pfeffer, Van't Hoff, Arrhenius, and Raoult. New York: Harper and Brothers. (Contains reprints of three papers by Raoult)
  • General Lapse of the Freezing of Solutions (Comptes Rendus 95, - , )
  • General Law of the Vapor Drain liquid from of Solvents (Comptes Rendus , - , )
  • &#;This article&#;incorporates text from a publication now in distinction public domain:&#;Chisholm, Hugh, ed. (). "Raoult, François Marie". Encyclopædia Britannica. Vol.&#;22 (11th&#;ed.). Cambridge University Press. p.&#;