Freiherr Justus von Liebig (May 12, 1803 in Darmstadt, Germany - April 18, 1873 in Munich, Germany) was a German chemist. He made major contributions to agricultural and biological chemistry, and worked on the organization of organic chemistry.
Liebig studied at the University of Bonn, together with Karl Wilhelm Gottlob Kastner. When Kastner moved to the University of Erlangen, Liebig accompanied him and received his doctorate there in 1822. He then received a grant from the Hessian government to study in Paris. Through the influence of Alexander von Humboldt he was able to work in the private laboratory of Joseph Louis Gay-Lussac.
1824, he became professor at the University of Gießen. He was a professor at the University of Munich from 1852 to 1873. He became Freiherr (baron) in 1845. Liebig improved organic analysis, and discovered that plants feed on the nitrogen (actually microbes do the conversions to nitrogen componds) and carbon dioxide in the air, as well as on minerals in the soil. One of his most famous accomplishments was the invention of nitrogen-based fertilizer. He was also one of the first chemists to organize a laboratory as we know it today.