Jacobus Henricus van 't Hoff

Biography

Jacobus Henricus van 't Hoff Jr. was born on August 30, 1852, in Rotterdam, Netherlands, as the third of seven children in a doctor's family. He showed early talent in chemistry and mathematics and went to Delft University of Technology to study technology after finishing high school. Finding the courses too focused on practical applications, he moved to Leiden University for pure science, later studying under August Kekulé in Bonn and Adolphe Wurtz in Paris. He earned his doctorate at Utrecht University in 1874, the same year he published a short pamphlet that would change structural chemistry.

In September 1874, Van 't Hoff published a twelve-page pamphlet in Dutch titled 'Voorstel tot Uitbreiding der Tegenwoordig in de Scheikunde gebruikte Structuurformules in de Ruimte' (A Proposal for the Extension of Current Chemical Structural Formulas into Space). In it, he suggested that the four bonds of a carbon atom point towards the corners of a tetrahedron, an idea that explained why optical isomers exist in organic compounds. He developed this concept independently, at the same time as French chemist Joseph Le Bel, laying the groundwork for stereochemistry. In 1875, he expanded this work to predict the structures of allenes and cumulenes, including their axial chirality, showing an uncommon level of theoretical precision for the time.

Van 't Hoff became a professor at the University of Amsterdam from 1878 to 1896. There, he turned his focus to physical chemistry, studying the thermodynamics of chemical reactions and how substances behave in solution. His 1884 work 'Études de dynamique chimique' introduced the concept of reaction order and provided a mathematical approach to chemical equilibrium and reaction rates. He created what is now called the Van 't Hoff equation, linking the change in the equilibrium constant of a reaction to temperature. In 1887, he published his significant study on osmotic pressure in dilute solutions, showing a formal similarity between the osmotic pressure of a dissolved substance and the pressure exerted by an ideal gas, through what is now known as the Van 't Hoff factor.

In 1896, he took a job at the Prussian Academy of Sciences in Berlin, where he spent the rest of his career. There, he focused on the geology and chemistry of oceanic salt deposits, especially the Stassfurt deposits in Germany, using physical chemistry to understand how mineral layers formed from ancient seas. This work connected chemistry, geology, and physics. In 1901, he received the Nobel Prize in Chemistry for his discovery of the laws of chemical dynamics and osmotic pressure in solutions. He passed away in Berlin on March 1, 1911, after a long illness, survived by his wife Johanna Francina Mees, whom he had married in 1878.