Van't Hoff theory. Biography. Chemical dynamics and kinetics

In the list of Nobel Prize winners in chemistry, Van't Hoff's name is at the top. He received the Nobel Prize in 1901 "for the discovery of the laws of chemical dynamics and osmotic pressure in solutions."

Jacob-Hendrik Van't Hoff (1852-1911) - one of the outstanding physical chemists, founders of modern physical chemistry - was born in Rotterdam (Holland) in the family of a doctor. Jacob had four brothers and two sisters. Two of the brothers died in infancy. Jacob's sister, eight-year-old Maria, who was three years older than him, died of tuberculosis.

In 1874, at the University of Utrecht, Van't Hoff defended his doctoral thesis on the study of certain organic acids, and became a doctor of mathematics and natural philosophy. However, none of the universities in Holland found him a place to work, even he was denied the position of a chemistry teacher. For two years Van't Hoff had to give private lessons in chemistry and physics. It was not until 1876 that he received his first position as assistant professor at the veterinary school in Utrecht; here he became famous after the publication of work on the structures of molecules. In 1878 Van't Hoff was elected professor of chemistry, mineralogy and geology at the newly founded University of Amsterdam. In the same year, he marries the daughter of a merchant from Rotterdam, Jenny Mess, whom he has loved for a long time and with whom he will live until the end of his days.

In 1896, Van't Hoff was elected a full member of the Berlin Academy of Sciences, and he and his family moved to Berlin.

The last years of van't Hoff's life were overshadowed by the death of his relatives and friends: in 1902, at the age of 85, his father died, six years later, his son-in-law, the husband of his daughter Eugenia, shot himself, his younger brother died soon after; another daughter left for the US against her parents' wishes. At the beginning of 1907, Van't Hoff fell ill with pulmonary tuberculosis, was treated every summer, but the disease progressed, and in 1911 he died. His older brother, a doctor, later wrote that "the transition from life to death was quiet, completely in line with the only desire that he expressed in moments of consciousness."

The chemist Jacob Hendrik van't Hoff was one of those scientists for whom science was a true passion and the meaning of life. Even in early childhood, having felt his true calling, he did not step back from the intended path, working tirelessly, improving himself both as a scientist and as a person. The pinnacle of recognition of his work in the scientific field was the receipt of the Nobel Prize, as well as well-deserved reverence in the scientific world.

Van't Hoff is considered one of the most significant figures who influenced the development and formation of chemistry as a science.

The early years of van't Hoff

Van't Hoff was born into a revered and intelligent Dutch family, in which, however, his intentions to become a scientist were not very welcome. The hometown of the future chemist was Rotterdam, where he was born on August 30, 1852. The family was big. Jacob was the third child, after him four more were born. Jacob's father was a fairly successful practicing doctor, and at the same time he had a very interesting hobby - he was known as a subtle connoisseur and connoisseur of Shakespeare's work. Therefore, literature was traditionally loved in the house, and the growing Jacob also absorbed this love. Byron's work, in particular, had a very great influence on him.

The first educational institution of Jacob was the city high school in Rotterdam. The teachers immediately noticed Jacob's extraordinary ability to master the exact sciences, as well as a passionate love for poetry.

Parents, also seeing the giftedness of their son, dreamed of his brilliant career as an engineer. When Yakob began to show interest in chemical experiments and outlined the future of a scientist for himself, his relatives reacted rather coolly to such zeal, considering a scientific career not very promising. Therefore, contrary to the wishes of the son, the parents insisted on his admission to the Polytechnic School, located in Delft.

The talented young man must be given credit, because without having a particular passion for mastering the engineering profession, he was able to become the best graduate of the school on the course. This allowed Jacob to enter the prestigious Leiden University in 1871 without passing the entrance exams. But, having studied here at the natural-mathematical faculty, Jacob realized that the study of mathematics was not his way. Therefore, after only one year of study, van't Hoff decides to transfer to the university in Bonn to study chemistry, which he loves so much. The talented scientist Friedrich Kekule, who had already made a name for himself, became the leader of the young student.

The beginning of a scientific career

Two years spent in Bonn in scientific research under the guidance of Kekule brought the young chemist Jacob van't Hoff his first significant achievement - he discovered propionic acid, which is now used to produce certain drugs and herbicides. Seeing a promising scientist in van't Hoff, Kekule advises him to continue his scientific work already in Paris, under the guidance of Professor Charles Adolf Wurtz, a well-known specialist in the field of organic synthesis.

The result of work in Paris was the writing of a doctoral dissertation, which Van't Hoff successfully defended at the University of Utrecht, becoming a doctor of science at the age of 22.

A great resonance in the scientific world of that time was produced by an article written by van't Hoff, in which he explained the phenomenon, discovered at the beginning of the 19th century, of a change in the direction of the movement of a light beam when passing through some chemical substances in the form of crystals. According to van't Hoff, such a change in the flux of light in a molecule is caused by the appearance of special isomers that are mirror images with respect to each other. As often happens in the scientific world, almost simultaneously with van't Hoff, his colleague La Belle proposed such a theory, while both scientists came to the same conclusions, working independently of each other. To some chemists, such a theory seemed almost ridiculous and divorced from reality, but, despite this, in the end it was it that served as one of the foundations for the new science of stereochemistry, the field of study of which is the spatial structure of molecules.

Teaching activity and further scientific work

Despite the very outstanding abilities and non-standard approach to research, Van't Hoff's career as a chemist did not develop very rapidly. For some time, the main source of his income was private lessons in physics and chemistry, which in no way contributed to the prosperity of van't Hoff as a serious scientific figure. Later, in the same Utrecht, he receives an invitation to the post of teacher of physics at the school, and after a year he takes the place of a lecturer at the University of Amsterdam, a little later he becomes a professor in it. He devoted many years of his life to work here, regularly lecturing and doing research.

It must be said that Van't Hoff's success and achievements were greatly facilitated by his thorough professional knowledge in the field of mathematics, which not every chemist possessed. This allowed the scientist to approach the solution of many problems from a new angle, eventually reaching such significant heights in scientific activity. The Nobel Prize awarded to him in 1901 was the result of recognition of the inestimable importance of his work in the 80s of the 19th century in the field of chemical dynamics, on the topic of which van't Hoff created one of his most famous works, Essays on Chemical Dynamics.

In the late 1980s, van't Hoff became one of the founders of the Journal of Physical Chemistry. At this time, the already well-known scientist was a desirable candidate for professorships at various universities, in particular, he received an offer to become a professor at the flourishing University of Leipzig.

However, van't Hoff was in no hurry with the decision, since the management of the university in Amsterdam at that time planned the construction of a new chemical laboratory. However, soon the scientist decides to accept one of the offers, eventually moving to Berlin to work at a prestigious and well-known university in the German capital. Here, van't Hoff received excellent laboratory equipment at his disposal and was able to freely and completely devote himself to his beloved work.

The field of scientific research of the eminent Dutchman at that time was physical chemistry, he was also engaged in work on the study of enzymes. The results of all his works greatly influenced the formation of chemistry as a science, and the Nobel Prize received was the first awarded to a chemist.

Family

Back in 1878, van't Hoff married Johann Francine Mees, who, like him, was from Rotterdam. They had four children - two sons and two daughters.

Last years

The scientist spent the rest of his life living and working in Germany. He was a member of many scientific organizations and had honorary degrees not only in European but also in American universities. In addition to scientific activity, to which his whole life was devoted, Jacob van't Hoff never ceased to admire art, in particular, his beloved poetry. He was also very fond of philosophy, loved to spend time in nature.

The cause of death of the scientist was tuberculosis, at that time one of the most common and dangerous diseases. The great scientist died on March 1, 1911 in German Steglitz (today one of the districts of Berlin).

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After working for a short time at a sugar factory, V.-G. in 1871 he became a student of the Faculty of Natural Sciences and Mathematics at the University of Leiden. However, the very next year he moved to the University of Bonn to study chemistry under Friedrich August Kekule. Two years later, the future scientist continued his studies at the University of Paris, where he completed his dissertation. Returning to the Netherlands, he introduced her to the defense at the University of Utrecht.

Even at the very beginning of the 19th century. French physicist Jean Baptiste Biot noticed that the crystalline forms of certain chemicals can change the direction of the rays of polarized light passing through them. Scientific observations have also shown that some molecules (they are called optical isomers) rotate the plane of light in the opposite direction to that in which other molecules rotate it, although both the first and the second are molecules of the same type and consist of the same number of atoms. Observing this phenomenon in 1848, Louis Pasteur hypothesized that such molecules are mirror images of each other and that the atoms of such compounds are arranged in three dimensions.

In 1874, a few months before defending his dissertation, V.-G. published an 11-page article titled "An Attempt to Extend to Space the Present Structural Chemical Formulae. With an Observation on the Relationship Between Optical Activity and the Chemical Constituents of Organic Compounds").

In this article, he proposed an alternative version of the two-dimensional models that were used at that time to depict the structures of chemical compounds. V.-G. suggested that the optical activity of organic compounds is associated with an asymmetric molecular structure, with the carbon atom located in the center of the tetrahedron, and at its four corners there are atoms or groups of atoms that differ from each other. Thus, the interchange of atoms or groups of atoms located at the corners of a tetrahedron can lead to the appearance of molecules that are identical in chemical composition, but which are mirror images of each other in structure. This explains the differences in optical properties.

Two months later, in France, similar conclusions were reached by V.-G. his friend at the University of Paris, Joseph Achille Le Bel. Having extended the concept of a tetrahedral asymmetric carbon atom to compounds containing carbon-carbon double bonds (common edges) and triple bonds (common faces), V.-G. argued that these geometric isomers socialize the edges and faces of the tetrahedron. Since the theory of van't Hoff - Le Bel was extremely controversial, V.-G. did not dare to submit it as a doctoral dissertation. Instead, he wrote a dissertation on cyanoacetic and malonic acids, and in 1874 received his doctorate in chemistry.

Considerations V.-G. about asymmetric carbon atoms were published in a Dutch journal and did not make much of an impression until two years later his paper was translated into French and German. First, the van't Hoff-Le Bel theory was ridiculed by famous chemists such as A.V. Hermann Kolbe, who called it "fantastic nonsense, completely devoid of any factual basis and completely incomprehensible to a serious researcher." However, over time, it formed the basis of modern stereochemistry - the field of chemistry that studies the spatial structure of molecules.

The formation of the scientific career of V.-G. went slowly. At first, he had to give advertised private lessons in chemistry and physics, and only in 1976 did he receive a position as lecturer in physics at the Royal Veterinary School in Utrecht. The following year he became a lecturer (and later professor) of theoretical and physical chemistry at the University of Amsterdam. Here, for the next 18 years, he gave five lectures every week on organic chemistry and one lecture on mineralogy, crystallography, geology and paleontology, and also directed the chemical laboratory.

Unlike most chemists of his time, V.-G. had a solid background in mathematics. It was useful to the scientist when he took on the difficult task of studying the rate of reactions and the conditions that affect chemical equilibrium. As a result of the work done, V.-G. depending on the number of molecules involved in the reaction, he classified chemical reactions as monomolecular, bimolecular and multimolecular, and also determined the order of chemical reactions for many compounds.

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After the onset of chemical equilibrium in the system, both forward and reverse reactions proceed at the same rate without any final transformations. If the pressure in such a system increases (conditions change or the concentration of its components changes), the equilibrium point shifts so that the pressure decreases. This principle was formulated in 1884 by the French chemist Henri Louis Le Chatelier. In the same year, V.-G. applied the principles of thermodynamics in formulating the principle of mobile equilibrium resulting from temperature changes. At the same time, he introduced the commonly accepted today designation of the reversibility of a reaction by two arrows pointing in opposite directions. The results of his research V.-G. outlined in "Essays on chemical dynamics" ("Etudes de dynamique chimique"), published in 1884.

In 1811, the Italian physicist Amedeo Avogadro found that equal volumes of any gases at the same temperature and pressure contain the same number of molecules. V.-G. came to the conclusion that this law is also valid for dilute solutions. The discovery he made was very important, since all chemical reactions and exchange reactions within living beings occur in solutions. The scientist also experimentally established that the osmotic pressure, which is a measure of the tendency of two different solutions on both sides of the membrane to equalize the concentration, in weak solutions depends on the concentration and temperature and, therefore, obeys the gas laws of thermodynamics. Conducted by V.-G. studies of dilute solutions were the rationale for the theory of electrolytic dissociation by Svante Arrhenius. Subsequently, Arrhenius moved to Amsterdam and worked with V.-G.

In 1887 V.-G. and Wilhelm Ostwald took an active part in the creation of the "Journal of Physical Chemistry" ("Zeitschrift fur Physikalische Chemie"). Ostwald had shortly before taken the vacant position of professor of chemistry at the University of Leipzig. V.-G. also offered this position, but he rejected the offer, as the University of Amsterdam announced its readiness to build a new chemical laboratory for the scientist. However, when V.-G. it became obvious that the pedagogical work carried out by him in Amsterdam, as well as the performance of administrative duties, interfere with his research activities, he accepted the offer of the University of Berlin to take the place of professor of experimental physics. It was agreed that he would give lectures here only once a week and that a fully equipped laboratory would be placed at his disposal. This happened in 1896.

Working in Berlin, V.-G. engaged in the application of physical chemistry to solving geological problems, in particular in the analysis of oceanic salt deposits in Stasfurt. Until the First World War, these deposits almost completely provided potassium carbonate for the production of ceramics, detergents, glass, soap, and especially fertilizers. V.-G. also began to study the problems of biochemistry, in particular the study of enzymes, which serve as catalysts for the chemical changes necessary for living organisms.

In 1901 V.-G. became the first winner of the Nobel Prize in Chemistry, which was awarded to him "in recognition of the great importance of his discovery of the laws of chemical dynamics and osmotic pressure in solutions." Representing V.-G. on behalf of the Royal Swedish Academy of Sciences, S.T. Odner called the scientist the founder of stereochemistry and one of the creators of the theory of chemical dynamics, and also emphasized that the research of V.-G. "contributed significantly to the remarkable achievements of physical chemistry."

In 1878 V.-G. married the daughter of a Rotterdam merchant, Johanna Francine Mees. They had two daughters and two sons.

Through all his life V.-G. carried a keen interest in philosophy, nature, poetry. He died of pulmonary tuberculosis on March 1, 1911 in Germany, in Steglitz (now part of Berlin).

In addition to the Nobel Prize, V.-G. He was awarded the Davy Medal of the Royal Society of London (1893) and the Helmholtz Medal of the Prussian Academy of Sciences (1911). He was a member of the Royal Netherlands and Prussian Academies of Sciences, the British and American Chemical Societies, the American National Academy of Sciences and the French Academy of Sciences. V.-G. honorary degrees from Chicago, Harvard and Yale Universities.

The dependence of the rate of a chemical reaction on temperature is determined by the van't Hoff rule.

The Dutch chemist van't Hoff Jacob Hendrik, the founder of stereochemistry, in 1901 became the first Nobel Prize winner in chemistry. She was awarded to him for discovering the laws of chemical dynamics and osmotic pressure. Van't Hoff introduced ideas about the spatial structure of chemicals. He was sure that progress in fundamental and applied research in chemistry could be achieved by applying physical and mathematical methods. Having developed the doctrine of the rate of reactions, he created chemical kinetics.

The rate of a chemical reaction

So, the kinetics of chemical reactions is the study of the rate of flow, about what kind of chemical interaction occurs in the course of reactions, and about the dependence of reactions on various factors. Different reactions have different speeds.

The rate of a chemical reaction directly depends on the nature of the chemicals involved in the reaction. Some substances, such as NaOH and HCl, can react in fractions of a second. And some chemical reactions last for years. An example of such a reaction is the rusting of iron.

The rate of a reaction also depends on the concentration of the reactants. The higher the concentration of reactants, the higher the rate of the reaction. As the reaction proceeds, the concentration of the reactants decreases, and therefore the rate of the reaction also slows down. That is, at the initial moment, the speed is always higher than at any subsequent moment.

V \u003d (C end - C start) / (t end - t start)

The concentrations of the reagents are determined at regular intervals.

Van't Hoff's rule

An important factor on which the rate of reactions depends is temperature.

All molecules collide with others. The number of collisions per second is very high. But, nevertheless, chemical reactions do not proceed with great speed. This happens because during the course of the reaction, the molecules must assemble into an activated complex. And only active molecules can form it, the kinetic energy of which is sufficient for this. With a small number of active molecules, the reaction proceeds slowly. As the temperature rises, the number of active molecules increases. Therefore, the reaction rate will be higher.

Van't Hoff believed that the rate of a chemical reaction is a regular change in the concentration of reactants per unit time. But it is not always uniform.

Van't Hoff's rule states that for every 10° increase in temperature, the rate of a chemical reaction increases by 2-4 times .

Mathematically, Van't Hoff's rule looks like this:

where V 2 t2, but V 1 is the reaction rate at temperature t 1 ;

ɣ is the temperature coefficient of the reaction rate. This coefficient is the ratio of the rate constants at temperature t+10 And t.

So if ɣ \u003d 3, and at 0 ° C the reaction lasts 10 minutes, then at 100 ° C it will last only 0.01 sec. A sharp increase in the rate of a chemical reaction is explained by an increase in the number of active molecules with increasing temperature.

Van't Hoff's rule is applicable only in the temperature range of 10-400 o C. Do not obey the Van't Hoff rule and reactions in which large molecules participate.

JACOB VANT HOFF

Van't Hoff received the first Nobel Prize in Chemistry for discovering the laws of chemical dynamics and osmotic pressure. This high award marked the importance of the young field of science - physical chemistry.

A highly respected scientist, a member of fifty-two scientific societies and academies, an honorary doctorate from many higher educational institutions, Van't Hoff left behind a number of fundamental theories that are of continuing importance for chemistry today. The views, ideas and views of the scientist played a big role in developing the foundations of modern mineralogy, as well as in the development of biology. Van't Hoff entered the history of science as one of the founders of stereochemistry, the theory of chemical equilibrium and chemical kinetics, the osmotic theory of solutions, and chemical geology.

Jacob Henrik Van't Hoff was born on August 30, 1852 in the Netherlands, in Rotterdam, in the family of a doctor. Members of this family were repeatedly elected burgomasters, and held other elected positions in the city government.

Already in elementary school, teachers noticed the boy's love for music and poetry. In the future, he showed remarkable abilities for the exact natural sciences. After leaving school in 1869, Jacob entered the polytechnic in Delft. And here, in terms of knowledge, he significantly surpassed his fellow students, and therefore in 1871 he was admitted to Leiden University without an entrance exam. Later at this university Van't Hoff passed the candidate's examination.

But he did not like Leiden, and he went to Bonn to the famous chemist Kekule. After the discovery of propionic acid by young scientists, Kekule recommended his student to go to Paris to Professor Wurtz, a specialist in organic synthesis.

In Paris, Jacob became close to the French chemist-technologist Joseph Achille Le Bel. Both followed with interest Pasteur's research in the field of optical isomerism.

In December 1874, van't Hoff defended his doctoral dissertation at the University of Utrecht and in 1876 began teaching at the local veterinary school. In the autumn of 1874, he published in Utrecht a short paper with a long title: "A proposal for the application in space of modern structural chemical formulas, together with notes on the relationship between the optical rotational power and the chemical constitution of organic compounds."

Van't Hoff introduced provisions into science that made it possible to consider the structure of chemical compounds from new positions. The notion that four hydrogen atoms in a methane molecule are evenly distributed in space and therefore one can speak of a tetrahedral shape of the molecule brings us back to Kekule's views. In the model proposed by van't Hoff, the four valences of the carbon atom are directed to the vertices of the tetrahedron, in the center of which this atom is located. Using such a model, van't Hoff suggested that due to the bonding of atoms or atomic groups with carbon, the tetrahedron could be asymmetric, and suggested an asymmetric carbon atom. He wrote: “In the case when the four affinities of the carbon atom are saturated with four different monovalent groups, it is possible to obtain two and only two different tetrahedra, which are a mirror image of one another and cannot be mentally combined in any way, that is, we are dealing with two structural formulas in space.

Van't Hoff's new article "Chemistry in Space" (1875), where he expressed all these considerations, served as the beginning of a new stage in the development of organic chemistry. Soon he received a letter from Professor Wislicenus, one of the most famous experts in this field: “I would like to get permission for the translation of your article into German by my assistant Dr. Hermann. Your theoretical development brought me great joy. I see in it not only an extremely ingenious attempt to explain hitherto incomprehensible facts, but I also believe that it will acquire epoch-making significance in our science.”

The translation of the article was published in 1876. By this time, van't Hoff had secured a position as an assistant in physics at the Veterinary Institute in Utrecht.

A large role in popularizing the new views of van't Hoff unwittingly went to Professor G. Kolbe from Leipzig. In a harsh form, he expressed his remarks about the article of the Dutch scientist: “Some doctor Ya.G. van't Hoff of the Veterinary Institute in Utrecht seems to have no taste for precise chemical research. It is much more convenient for him to sit on a Pegasus (probably borrowed from the Veterinary Institute) and proclaim in his "Chemistry in Space" that, as it seemed to him during a bold flight to chemical Parnassus, atoms are located in interplanetary space. Naturally, everyone who read this sharp rebuke was interested in Van't Hoff's theory. Thus began its rapid spread in the scientific world. Now van't Hoff could repeat the words of his idol Byron: "One morning I woke up a celebrity." A few days after the publication of the article, Kolbe van't Hoff was offered a teaching position at the University of Amsterdam, and from 1878 he became a professor of chemistry.

From 1877 to 1896 Van't Hoff was professor of chemistry, mineralogy and geology at the newly founded University of Amsterdam. His wife, Jenny Van't Hoff-Mees, was always by his side. She managed to deal not only with the house and children, but also managed to create a real creative atmosphere for her husband.

van't Hoff's interest in the search for the most general patterns reappeared in his great work Views on Organic Chemistry. But soon the scientist turned to the study of chemical dynamics. He outlined his views on this issue in the book Essays on Chemical Dynamics (1884).

Van't Hoff developed the doctrine of the rate of reactions and thereby created the foundations of chemical kinetics. He defined the reaction rate as a regular, but far from always uniform, change in the concentration of reactants per unit time. He managed to formulate this pattern in a general mathematical form. The establishment of the dependence of the reaction rate on the number of interacting molecules, as well as the closely related new ideas of van't Hoff on the nature of chemical equilibrium, significantly contributed to the significant progress of theoretical chemistry.

At the same time, it was found that the chemical equilibrium, considered by van't Hoff as the result of two oppositely directed reactions proceeding at the same rate (a reversible process), depends on temperature. van't Hoff connected the concept of chemical equilibrium with the two principles of thermodynamics already known at that time. The most important result of this work was the derivation by van't Hoff of a mathematical formula that reflected the relationship between the temperature and heat of reaction with the equilibrium constant. This regularity is now known as the reaction isochore equation derived by van't Hoff.

Another major contribution of van't Hoff to theoretical chemistry during his Amsterdam period was the discovery of the analogy between osmotic and gas pressure. Based on the empirical laws formulated by Raoult about raising the boiling point and lowering the freezing point of solutions, Van't Hoff developed the osmotic theory of solutions in 1885.

K. Manolov tells in his book how the scientist came to this discovery: “Why not imagine the system in the osmometer "water - semi-permeable partition - solution" in the form of a cylinder with a piston? The solution is at the bottom of the cylinder, the piston is a baffle, and above it is water. This is the basic method of thermodynamics. The principles of gas thermodynamics also apply to the properties of dilute solutions.”

Van't Hoff drew a cylinder with a piston, in the space under the piston he wrote "Solution", and above the piston - "Water". The arrows pointing from the solution to the water showed that there was pressure in the solution, which tends to push the piston up.

“First, you need to calculate how much work is required for the piston to move up under the action of osmotic pressure, but you can also find out how much work is needed to return the piston down, overcoming osmotic pressure.”

Van't Hoff did the math, filling the sheet with formulas, and here it is, the end result!

“Incredible! The dependence is exactly the same as for gases! The expression is absolutely identical to the Clausius-Clapeyron equation!” Van't Hoff took the sheet and repeated all the calculations. “Same result! The laws of osmotic pressure are identical to the laws of gases. If the constant also has the same value, then one can consider the molecules of the dilute substance as molecules of a gas, imagining that the solvent is removed from the vessel. The constant can be calculated from the Pfeffer data.” He picked up the notebook again, and the pen quickly slid over the paper. For sugar solutions, the constant had the same value as the gas constant. The analogy was complete.

Van't Hoff found that dissolved molecules produce an osmotic pressure equal to the pressure that the same molecules would exert if they occupied a volume equal to the volume of the solution in the gaseous state. This fundamental discovery showed the unity of the laws of physics and chemistry (although the causes of osmotic pressure have not been revealed).

Van't Hoff also had a great influence on the further development of the theory of dissociation, having studied in his work "Chemical equilibrium in systems of gases and dilute solutions" (1886).

In March 1896 Van't Hoff left Amsterdam, moving to Berlin at the invitation of the Prussian Academy of Sciences. In accordance with the proposal of Max Planck and Emil Fischer, a special research laboratory was created for Van't Hoff at the Academy of Sciences, and the scientist himself was immediately elected its full member and honorary professor at the University of Berlin.

In Germany, he carried out extensive experimental and theoretical work, which helped to establish the conditions for the formation of potassium salt deposits and create a rational technology for their processing.

The scientist was in America when he learned that he received the first Nobel Prize in Chemistry "in recognition of the great importance of his discovery of the laws of chemical dynamics and osmotic pressure in solutions." On December 10, 1901, outstanding scientists of the world gathered in Stockholm. The solemn ceremony in the festively lit hall of the Swedish Academy of Sciences was truly unforgettable.

In the evening, at a banquet, van't Hoff had the opportunity to express his heartfelt thanks for the great honor he was bestowed upon the Committee for the Nobel Prizes in Chemistry and personally to its chairman, Professor P. Kleve.

Representing the scientist on behalf of the Royal Swedish Academy of Sciences, S.T. Odner called the scientist the founder of stereochemistry and one of the creators of the theory of chemical dynamics, and also emphasized that Van't Hoff's research "made a significant contribution to the remarkable achievements of physical chemistry."

In the following days, according to the requirements of the Nobel Committee, the awardees had to make reports on the scientific achievements for which they were awarded the prize. Van't Hoff spoke about the theory of solutions in his lecture.

The scientist continued to work, but a long-standing serious illness prevented van't Hoff from studying the synthetic action of enzymes in a living plant organism.