Dutch physicist (1837–1923)

Van der Waals was born at Leiden in the Netherlands. He was largely self-taught in science and he originally worked as a school teacher. He later managed to study at the University of Leiden, having been exempted from the Latin and Greek entrance requirements. In 1877 he became professor of physics at the University of Amsterdam.

Van der Waals studied the kinetic theory of gases and fluids and in 1873 presented his influential doctoral thesis, On the Continuity of the Liquid and Gaseous States. His main work was to develop an equation (the van der Waals equation) that – unlike the gas laws of Robert Boyle and Jacques Charles – applied to real gases. The Boyle–Charles law, strictly speaking, applies only to ‘ideal’ gases, but can be derived from the kinetic theory given the assumptions that there are no attractive forces between gas molecules and that the molecules themselves have zero volume.

Since the molecules do have attractive forces and volume (however small), van der Waals introduced into the theory two further constants to take these properties into account. Initially these constants had to be specific to each gas since the size of the molecules and the attractive force between them is different for each gas. Further work by van der Waals yielded the law of corresponding states – an equation that is the same for all substances. His valuable results enabled James Dewar and Heike Kamerlingh-Onnes to work out methods of liquefying the permanent gases.

In 1910 van der Waals was awarded the Nobel Prize for physics for his work on the equation of state. The weak electrostatic attractive forces between molecules and between atoms are called van der Waals forces in his honor.

The Dutch physicist Johannes Diderik van der Waals (1837-1923) did pioneering studies on the equation of state of liquids and gases, for which he received the Nobel Prize for physics in 1910.

Johannes van der Waals was born on Nov. 23, 1837, in Leiden, the son of Jacobus van der Waals and Elizabeth van den Burg. His life is a classic illustration of the fact that lack of proper educational opportunities is not an insurmountable obstacle to greatness in science, provided one's potential is matched by one's determination. Following the completion of his elementary and secondary education, he taught elementary school in Leiden with his mind fixed on much higher goals. His thirst for knowledge had at first to be satisfied with reading in his spare time, but during the years 1862-1865 he followed courses at the University of Leiden and obtained the certification to teach mathematics and physics in high schools. In 1864 he married Anna Magdalena Smit, who soon died, leaving him with four small children.

While Van der Waals served as director of a high school in The Hague, a new law removed classical languages from the list of compulsory courses for science students at universities, and he passed in 1873 the examinations for doctor's degree in physics. His dissertation, On the Continuity of the Gaseous and Liquid States, revealed him at one stroke as a most original master of physics. In fact James Clerk Maxwell remarked, when he learned of the dissertation's contents, "The name of Van der Waals will soon be among the foremost in molecular science."

Van der Waals argued that R. J. E. Clausius's derivation of Robert Boyle's gas law from statistical mechanics had to be supplemented by new considerations if it was to hold for real gases and their transformation into liquids. The new consideration was the "principle of continuity, " by which Van der Waals meant that from the viewpoint of statistical mechanics there could be no basic difference between the gaseous and the liquid states. In addition he noted the need for considering two factors, the volume of molecules and their mutual attraction. He succeeded in relating these two factors to the critical temperature, pressure, and volume, or the critical point. It therefore followed that the equation of state could be expressed in a form independent of any particular gas or liquid.

This in turn led to the most momentous part of Van der Waals's research, the law of corresponding states, formulated in 1880. According to it, the whole range of behavior of a substance can be predicted once its critical point has been ascertained. This result played a crucial role in the efforts leading to the liquefaction of hydrogen (1898) and of helium (1908). His other principal achievement consisted in the combination of the law of corresponding states with the second law of thermodynamics, which he outlined in 1890 in his first treatise on the theory of binary solutions.

In 1876 Van der Waals became the first professor of physics at the newly established University of Amsterdam. His son, Johannes Diderik, Jr., was the next occupant of the chair. Van der Waals died in Amsterdam on March 8, 1923.

Further Reading

Biographical information on Van der Waals and accounts of his work are in N. de V. Heathcote, Nobel Prize Winners in Physics, 1901-1950 (1953), and Nobel Foundation, Nobel Lectures: Physics, 1901-1921 (1967).

For more information on Johannes Diederik van der Waals, visit Britannica.com.

(yōhä'nəs dē'dərĭk vän dər väls) , 1837–1923, Dutch physicist. It had been known for some time that the behavior of real gases differs from that of an ideal gas as predicted by thermodynamics and the kinetic-molecular theory of gases. Van der Waals was led to the hypothesis of the continuity of the gaseous and liquid states of matter by combining the kinetic theory of gases with Laplace's theory of capillarity. In his theory of corresponding states (1880) he presented an equation of state (now named for him) for homogeneous substances in terms of pressure, volume, and temperature (see gas laws); unlike the ideal gas law, his equation contains constant factors (different for each real substance) to account for the fact that molecules are of finite size and experience weak forces of mutual attraction (now called van der Waals forces). For that work and for discovering the law of binary mixtures he received the 1910 Nobel Prize in Physics. He was professor (1877–1907) at the Univ. of Amsterdam.

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)