Nernst, Walther Hermann (1864–1941),
German physical chemist. One of the founders of modern physical chemistry, Nernst was a professor of chemistry first at Göttingen and then at Berlin. His research topics included the thermodynamics of chemical equilibrium, the theory of galvanic cells, the mechanism of photochemistry, and the properties of vapors at high temperature and of solids at low temperature. In 1888 he published his derivation of the law of diffusion for electrolytes in the simple case when only two kinds of ions are present. The formulation is now known as the Nernst equation. In 1889 in a more extensive study he developed the fundamental relationship between electromotive force and ionic concentration. Perhaps his most notable contribution was his formulation of the third law of thermodynamics in 1906, for which he was awarded the Nobel Prize for Chemistry in 1920.