Johannes Diderik van der Waals

Introduction

Johannes Diderik van der Waals was a Dutch physicist and thermodynamicist whose contributions to the theory of gases and liquids earned him a Nobel Prize in 1910.

Early Life

Johannes Diderik van der Waals was born on 23 November 1837 in Leiden in the Netherlands. He was the son of Jacobus van der Waals and Elisabeth van den Burg.

Family Background

Van der Waals’s father was a carpenter and hence, didn’t receive much formal education as a child. Although he managed to attend elementary school in his birthplace, he lacked knowledge in classical languages.

Early Education

With the elementary school he attended, Van der Waals was able to become a schoolteacher.

University Studies

Due to no knowledge in classical languages, Van der Waals wasn’t allowed to take academic examinations but he continued studying at Leiden University in his spare time during 1862-65.

Career Development

Through this way, Van der Waals obtained teaching certificates in mathematics and physics.

Teaching Career

Van der Waals started his career as a school teacher at a secondary school at Deventer. In 1866 he moved to The Hague, first as teacher and later as Director of one of the secondary schools in that town.

Return to Study

However, he was an avid reader and taught Van der Waals return to study physics at the University of Leiden where he obtained his doctorate in 1873 with his thesis on the continuity of gaseous and liquid states.

Major Contributions

He introduced the concept of intermolecular forces in his thesis which he called “van der Waals forces” to explain the deviations of real gases from the ideal gas law.

Van der Waals Equation of State

He also derived a general equation of state that could describe both gases and liquids as well as their phase transitions which was named the “van der Waals equation of state”. The equation contained two parameters, an and b, that account for the attraction and repulsion between molecules.

Critical Point Concept

Van der Waals then developed the concept of the critical point which is the temperature at which the distinction between gas and liquid disappears. He used his equation of state to measure the critical constants for several gases which was later confirmed by experiments.

Personal Life

Van der Waals was married to Anna Magdalena Smit in 1865. The couple had four children.

Later Life and Death

Van der Waals was also a widower before he died. He lost his wife to tuberculosis at age 34 and this badly affected him. He remained unmarried even after her death.

Legacy

He passed away in Amsterdam at the age of 85.