Van't Hoff Jacob Hendrik

(30.VIII 1852 - 1.III 1911)
Dutch chemist. Born in Rotterdam. He graduated from the Polytechnic School in Delft (1871). Improve education in Leiden and Bonn (y F. A. Kekulц? von Stradonitz) University, Graduate School of Medicine in Paris (y W. A. Wurtz) and Utrecht University (Ph.D., 1874). Since 1876, Mr.. worked in the veterinary school in Utrecht, in 1878 -1896 years. - Professor of Amsterdam, in 1896 - 1911 he. - University of Berlin.

One of the founders of physical chemistry and stereochemistry. Considering the various cases of optical isomerism of organic compounds, the first time simultaneously with M. A. Le Belem and independently formulated (1874) theory of the spatial arrangement of atoms in molecules of organic compounds, which lies at the basis of modern stereochemistry. Put forward ideas about the direction of units of affinity of the carbon atom at the corners of a tetrahedron, the presence of two stereoisomers of a compound containing a carbon atom with four different substituents, and on the edge connecting the tetrahedra in the presence of the double bond. Predicted isomers allene compounds. Deduced rule, . which the molecular rotation of compounds with multiple asymmetric centers is the algebraic sum of shares of the molecular rotations of the asymmetric centers, . so-called rotoforov (the principle of additivity of optical van't Hoff),
. Investigated (from 1880-ies.) Kinetics of reactions and chemical affinity. Proposed a classification of chemical reactions. Found that with increasing temperature at 10 б° C, the reaction rate increases by 2-4 times (usually van't Hoff). Deduced one of the basic equations of chemical thermodynamics - the equation of isochores, . expressing the dependence of the equilibrium constant on temperature and the thermal effect, . as well as the chemical equation of the isotherm, . expressing the dependence of the chemical affinity of the equilibrium constant of reaction at constant temperature,
. Published (1884) work 'Sketches of chemical dynamics', in which formulated the basic postulates of chemical kinetics. For the first time proposed to assess the reactivity of substances by the rate constants of reactions, . that translation of the main thesis of structural chemistry - the dependence of the reactivity of the structure - on the rails under the quantitative chemical kinetics,
. He put (1886 - 1889 gg.) Basis of the quantity theory of dilute solutions, . showing, . that the solutes are similar to substances in a gaseous state and that to dilute solutions can be applied simple laws (including Avogadro's law),
. Deduced the law of osmotic pressure (van't Hoff's law). Distributed (1890) their ideas about solutions to the homogeneous solid mixtures, laying the foundations of the theory of solid solutions. Extended analogy between the polymorphic transformations and the transition from one state to another for a double salt.

Member of several scientific academies and scientific societies. Foreign Cor-Cor. Petersburg Academy of Sciences (since 1895).

Nobel Prize (1901).