Walther Hermann Nernst, ForMemRS (25 June 1864 – 18 November 1941) was a German chemist who is known for his theories behind the calculation of chemical affinity as embodied in the third law of thermodynamics, for which he won the 1920 Nobel Prize in chemistry. Nernst helped establish the modern field of physical chemistry and contributed to electrochemistry, thermodynamics and solid state physics. He is also known for developing the Nernst equation.
Nernst was born in Briesen in West Prussia (now Wąbrzeźno, Poland) as son of Gustav Nernst (1827–1888) and Ottilie Nerger (1833–1876). His father was a country judge. Nernst had three older sisters and one younger brother. The third sister died due to cholera. Nernst went to elementary school at Graudenz. He studied physics and mathematics at the universities of Zürich, Berlin, Graz and Würzburg, where he received his doctorate 1887. In 1889, he finished his habilitation at University of Leipzig.
It was said that Nernst was mechanically minded in that he was always thinking of ways to apply new discoveries to industry. Nernst's hobbies included hunting and fishing.