Dutch chemist who suggested that asymmetry in molecules resulted from the physical arrangement of atoms. Arguing from the number of observed isomers, he suggested that the carbon atom bonded tetrahedrally. He explained the rotation of plane polarized light using this model. (A similar theory was introduced by Le Bel.) The theory of spatial distribution was attacked by chemists such as Kolbe. With Ostwald, he established the first journal of physical chemistry.

In 1886, Van't Hoff proposed that dilute solutions have similar properties to gases. He studied osmotic pressure, which occurs when a solution is separated from a pure solvent by a membrane which does not allow solute to pass and results on a greater pressure on the solution side. Osmotic pressure plays a vital role in plant and animal life, and can be used to determine molecular weights. For this work, Van't Hoff was awarded the first Nobel prize in chemistry in 1901.