Short answers, pulled from the story.
Walther Nernst won the Nobel Prize in Chemistry in 1920 for his work on thermochemistry, specifically his formulation of the New Heat Theorem, which became the third law of thermodynamics. The theorem showed that as temperature approaches absolute zero, entropy approaches zero while free energy remains above zero, allowing chemists to calculate the equilibrium points of chemical reactions from heat measurements.
The Nernst glower was a solid-body light source with a filament made of rare-earth oxides, invented as an alternative to the carbon filament lamp. It operates best in wavelengths from 2 to 14 micrometers and remains important in infrared spectroscopy. Nernst sold the patent for one million marks.
Nernst proposed using tear gas shells to drive defenders out of trenches. When that idea was tested, Fritz Haber observed and argued it was inefficient, proposing instead a cloud of heavier-than-air poisonous gas. The first chlorine cloud attack followed on the 22nd of April 1915. Nernst went on to serve as a Staff Scientific Advisor directing explosives research and was awarded the Iron Cross first class and the Pour le Mérite.
The Neo-Bechstein-Flügel was an electric piano developed in 1930 by Nernst in association with the Bechstein and Siemens companies. It replaced the traditional sounding board with vacuum tube amplifiers and used electromagnetic pickups to produce electronically modified and amplified sound, in the same way as an electric guitar.
When a colleague was dismissed in 1933 for being Jewish, Nernst immediately sought to find him a position and declined to fill out a government form on racial origins. He was removed from his professorship and the board of the Kaiser Wilhelm Institute. Two of his three daughters had married Jewish men and emigrated after Hitler came to power, one to England and one to Brazil.
Nernst was buried three times. He was first interred near Zibelle, Germany, the place where he died on the 18th of November 1941. His remains were then moved to Berlin for a second burial, and finally moved a third time to Göttingen, where he now lies near the graves of Max Planck, Otto Hahn, and Max von Laue.