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35-577: Jacobus Henricus van 't Hoff Jr. ( Dutch: [vɑn (ə)t ˈɦɔf] ; 30 August 1852 – 1 March 1911) was a Dutch physical chemist . A highly influential theoretical chemist of his time, van 't Hoff was the first winner of the Nobel Prize in Chemistry . His pioneering work helped found the modern theory of chemical affinity , chemical equilibrium , chemical kinetics , and chemical thermodynamics . In his 1874 pamphlet, Van 't Hoff formulated

70-447: A chemical compound. Spectroscopy is the related sub-discipline of physical chemistry which is specifically concerned with the interaction of electromagnetic radiation with matter. Another set of important questions in chemistry concerns what kind of reactions can happen spontaneously and which properties are possible for a given chemical mixture. This is studied in chemical thermodynamics , which sets limits on quantities like how far

105-794: A degree of chemical technologist . He passed all his courses in two years, although the time assigned to study was three years. Then he enrolled at University of Leiden to study chemistry. He then studied in Bonn , Germany, with August Kekulé and in Paris with Adolphe Wurtz . He received his doctorate under Eduard Mulder at the University of Utrecht in 1874. In 1878, van 't Hoff married Johanna Francina Mees. They had two daughters, Johanna Francina (1880–1964) and Aleida Jacoba (1882–1971), and two sons, Jacobus Henricus van 't Hoff III (1883–1943) and Govert Jacob (1889–1918). Van 't Hoff died at

140-439: A limited extent, quasi-equilibrium and non-equilibrium thermodynamics can describe irreversible changes. However, classical thermodynamics is mostly concerned with systems in equilibrium and reversible changes and not what actually does happen, or how fast, away from equilibrium. Which reactions do occur and how fast is the subject of chemical kinetics , another branch of physical chemistry. A key idea in chemical kinetics

175-476: A mixture, is a special case of another key concept in physical chemistry, which is that to the extent an engineer needs to know, everything going on in a mixture of very large numbers (perhaps of the order of the Avogadro constant , 6 x 10 ) of particles can often be described by just a few variables like pressure, temperature, and concentration. The precise reasons for this are described in statistical mechanics ,

210-502: A new method for determining the order of a reaction using graphics and applied the laws of thermodynamics to chemical equilibria. He also introduced the modern concept of chemical affinity . In 1886, he showed a similarity between the behaviour of dilute solutions and gases. In 1887, he and German chemist Wilhelm Ostwald founded an influential scientific magazine named Zeitschrift für physikalische Chemie (" Journal of Physical Chemistry "). He worked on Svante Arrhenius 's theory of

245-464: A professor of chemistry, mineralogy , and geology at the University of Amsterdam for almost 18 years before eventually becoming the chairman of the chemistry department. In 1896, van 't Hoff moved to Germany, where he finished his career at the University of Berlin in 1911. In 1901, he received the first Nobel Prize in Chemistry for his work with solutions. His work showed that very dilute solutions follow mathematical laws that closely resemble

280-402: A reaction can proceed, or how much energy can be converted into work in an internal combustion engine , and which provides links between properties like the thermal expansion coefficient and rate of change of entropy with pressure for a gas or a liquid . It can frequently be used to assess whether a reactor or engine design is feasible, or to check the validity of experimental data. To

315-550: A specialty within physical chemistry which is also shared with physics. Statistical mechanics also provides ways to predict the properties we see in everyday life from molecular properties without relying on empirical correlations based on chemical similarities. The term "physical chemistry" was coined by Mikhail Lomonosov in 1752, when he presented a lecture course entitled "A Course in True Physical Chemistry" ( Russian : Курс истинной физической химии ) before

350-585: A time when the only job van 't Hoff could find was at the Veterinary School in Utrecht. In these early years his theory was largely ignored by the scientific community, and was sharply criticized by one prominent chemist, Hermann Kolbe . Kolbe wrote: "A Dr. J. H. van 't Hoff of the Veterinary School at Utrecht has no liking, apparently, for exact chemical investigation. He has considered it more convenient to mount Pegasus (apparently borrowed from

385-586: Is probably the most important 20th century development. Further development in physical chemistry may be attributed to discoveries in nuclear chemistry , especially in isotope separation (before and during World War II), more recent discoveries in astrochemistry , as well as the development of calculation algorithms in the field of "additive physicochemical properties" (practically all physicochemical properties, such as boiling point, critical point, surface tension, vapor pressure, etc.—more than 20 in all—can be precisely calculated from chemical structure alone, even if

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420-443: Is that for reactants to react and form products , most chemical species must go through transition states which are higher in energy than either the reactants or the products and serve as a barrier to reaction. In general, the higher the barrier, the slower the reaction. A second is that most chemical reactions occur as a sequence of elementary reactions , each with its own transition state. Key questions in kinetics include how

455-821: The British Chemical Society in London, the Royal Netherlands Academy of Arts and Sciences (1892), American Chemical Society (1898), the Académie des Sciences in Paris (1905), and the Netherlands Chemical Society (1908). Of his numerous distinctions, van 't Hoff regarded winning the first Nobel Prize in Chemistry as the culmination of his career. The following are named after him: On 14 May 2021, asteroid 34978 van 't Hoff , discovered by astronomers with

490-457: The Palomar–Leiden survey in 1977, was named in his memory. Physical chemistry Physical chemistry, in contrast to chemical physics , is predominantly (but not always) a supra-molecular science, as the majority of the principles on which it was founded relate to the bulk rather than the molecular or atomic structure alone (for example, chemical equilibrium and colloids ). Some of

525-742: The United States with his family. For a brief time he acted as assistant to Harvard chemist Eben Horsford , and in 1855 was appointed lecturer at the Mechanics' Institute in New York. Returning to Europe in 1856, he continued to study chemistry with Wilhelm Heinrich Heintz at the University of Halle. In 1860, he began lecturing at the University of Zürich , and at the Swiss Polytechnical Institute and by 1868 he

560-430: The University of Leipzig , where he died on 6 December 1902. By the late 1860s, Wislicenus devoted his research to organic chemistry. His work on the isomeric lactic acids from 1868 to 1872 resulted in the discovery of two substances with different physical properties but with an identical chemical structure . He called this difference "geometrical isomerism". He would later promote J. H. van't Hoff 's theory of

595-534: The isomers found in nature. He shares credit for this with the French chemist Joseph Le Bel , who independently came up with the same idea. Three months before his doctoral degree was awarded, van 't Hoff published this theory, which today is regarded as the foundation of stereochemistry , first in a Dutch pamphlet in the fall of 1874, and then in the following May in a small French book entitled La chimie dans l'espace . A German translation appeared in 1877, at

630-651: The Veterinary School) and to proclaim in his ‘La chimie dans l’espace’ how, in his bold flight to the top of the chemical Parnassus, the atoms appeared to him to be arranged in cosmic space." However, by about 1880, support for van 't Hoff's theory by such important chemists as Johannes Wislicenus and Viktor Meyer brought recognition. In 1884, Van 't Hoff published his research on chemical kinetics, titled Études de Dynamique chimique ( "Studies in Chemical Dynamics" ), in which he described

665-415: The age of 58, on 1 March 1911, at Steglitz , near Berlin, of tuberculosis . Van 't Hoff earned his earliest reputation in the field of organic chemistry . In 1874, he accounted for the phenomenon of optical activity by assuming that the chemical bonds between carbon atoms and their neighbors were directed towards the corners of a regular tetrahedron . This three-dimensional structure accounted for

700-474: The chemical molecule remains unsynthesized), and herein lies the practical importance of contemporary physical chemistry. See Group contribution method , Lydersen method , Joback method , Benson group increment theory , quantitative structure–activity relationship Some journals that deal with physical chemistry include Historical journals that covered both chemistry and physics include Annales de chimie et de physique (started in 1789, published under

735-414: The development of quantum mechanics into quantum chemistry from the 1930s, where Linus Pauling was one of the leading names. Theoretical developments have gone hand in hand with developments in experimental methods, where the use of different forms of spectroscopy , such as infrared spectroscopy , microwave spectroscopy , electron paramagnetic resonance and nuclear magnetic resonance spectroscopy ,

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770-713: The dissociation of electrolytes and in 1889 provided physical justification for the Arrhenius equation . In 1896, he became a professor at the Prussian Academy of Sciences in Berlin. His studies of the salt deposits at Stassfurt were an important contribution to Prussia's chemical industry. Van 't Hoff became a lecturer in chemistry and physics at the Veterinary College in Utrecht . He then worked as

805-496: The laws describing the behavior of gases . In 1885, Van 't Hoff was appointed as a Member of the Royal Netherlands Academy of Arts and Sciences . In 1904, he was elected as a member to the American Philosophical Society . Other distinctions include honorary doctorates from Harvard and Yale (1901), Victoria University , the University of Manchester (1903), and University of Heidelberg (1908). He

840-402: The leading figures in physical chemistry in the late 19th century and early 20th century. All three were awarded the Nobel Prize in Chemistry between 1901 and 1909. Developments in the following decades include the application of statistical mechanics to chemical systems and work on colloids and surface chemistry , where Irving Langmuir made many contributions. Another important step was

875-683: The name given here from 1815 to 1914). Johannes Wislicenus Johannes Wislicenus ( German pronunciation: [joˈhanəs vɪsliˈt͜seːnʊs] ; 24 June 1835 – 5 December 1902) was a German chemist , most famous for his work in early stereochemistry . The son of the radical Protestant theologian Gustav Wislicenus , Johannes was born on 24 June 1835 in Kleineichstedt (now part of Querfurt , Saxony-Anhalt ) in Prussian Saxony , and entered University of Halle-Wittenberg in 1853. In October 1853 he immigrated to

910-558: The properties of chemical compounds from a description of atoms and how they bond is one of the major goals of physical chemistry. To describe the atoms and bonds precisely, it is necessary to know both where the nuclei of the atoms are, and how electrons are distributed around them. Quantum chemistry , a subfield of physical chemistry especially concerned with the application of quantum mechanics to chemical problems, provides tools to determine how strong and what shape bonds are, how nuclei move, and how light can be absorbed or emitted by

945-412: The rate of reaction depends on temperature and on the concentrations of reactants and catalysts in the reaction mixture, as well as how catalysts and reaction conditions can be engineered to optimize the reaction rate. The fact that how fast reactions occur can often be specified with just a few concentrations and a temperature, instead of needing to know all the positions and speeds of every molecule in

980-432: The relationships that physical chemistry strives to understand include the effects of: The key concepts of physical chemistry are the ways in which pure physics is applied to chemical problems. One of the key concepts in classical chemistry is that all chemical compounds can be described as groups of atoms bonded together and chemical reactions can be described as the making and breaking of those bonds. Predicting

1015-459: The students of Petersburg University . In the preamble to these lectures he gives the definition: "Physical chemistry is the science that must explain under provisions of physical experiments the reason for what is happening in complex bodies through chemical operations". Modern physical chemistry originated in the 1860s to 1880s with work on chemical thermodynamics , electrolytes in solutions, chemical kinetics and other subjects. One milestone

1050-434: The tetrahedral carbon atom, believing that it, together with the supposition that there are "specially directed forces, the affinity-energies", which determine the relative position of atoms in the molecule , afforded a method by which the spatial arrangement of atoms in particular cases may be ascertained by experiment. While at Würzburg, Wislicenus developed the use of ethyl aceto acetate in organic synthesis. However, he

1085-474: The theory of the tetrahedral carbon atom and laid the foundations of stereochemistry . In 1875, he predicted the correct structures of allenes and cumulenes as well as their axial chirality . He is also widely considered one of the founders of physical chemistry as the discipline is known today. The third of seven children, van 't Hoff was born in Rotterdam , Netherlands, 30 August 1852. His father

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1120-624: Was Jacobus Henricus van 't Hoff Sr., a physician, and his mother was Alida Kolff van 't Hoff. From a young age, he was interested in science and nature, and frequently took part in botanical excursions. In his early school years, he showed a strong interest in poetry and philosophy . He considered Lord Byron to be his idol. Against the wishes of his father, van 't Hoff chose to study chemistry . First, he enrolled at Delft University of Technology in September 1869, and studied until 1871, when he passed his final exam on 8 July and obtained

1155-555: Was Professor of Chemistry at the university. In 1870, he was chosen to succeed Georg Staedeler as Professor of General Chemistry at the Swiss Polytechnical Institute in Zürich, retaining also the position of full professor at the University of Zürich. In 1872, he succeeded Adolph Strecker in the chair of chemistry at University of Würzburg , and in 1885, he succeeded Hermann Kolbe as Professor of Chemistry at

1190-791: Was awarded the Davy Medal of the Royal Society in 1893 (along with Le Bel ), and elected a Foreign Member of the Royal Society (ForMemRS) in 1897 . He was awarded the Helmholtz Medal of the Prussian Academy of Sciences (1911), and appointed Knight of the French Legion of Honour (1894) and Senator in the Kaiser-Wilhelm-Gesellschaft (1911). Van 't Hoff became an Honorary Member of

1225-653: Was the publication in 1876 by Josiah Willard Gibbs of his paper, On the Equilibrium of Heterogeneous Substances . This paper introduced several of the cornerstones of physical chemistry, such as Gibbs energy , chemical potentials , and Gibbs' phase rule . The first scientific journal specifically in the field of physical chemistry was the German journal, Zeitschrift für Physikalische Chemie , founded in 1887 by Wilhelm Ostwald and Jacobus Henricus van 't Hoff . Together with Svante August Arrhenius , these were

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