Hermann Walther Nernst

views updated

Hermann Walther Nernst

1864-1941

German chemist who won the Nobel Prize in 1920 for his formulation of the third law of thermodynamics, also known as the Nernst heat theorem (1905). This law states that no substance can be cooled to absolute zero (no atomic motion), but as this limit is approached, the difference between the changes in the heat content and the free energy of a chemical system become zero. Nernst's law allowed for exact measurement of free energy changes and related chemical thermodynamics to quantum theory in physics.

More From encyclopedia.com