Justus von Liebig, who in 1824 had…

Justus von Liebig, who in 1824 had established the world's first major school of chemistry at the University of Giessen, has improved organic analysis with the Kaliapparat—a five-bulb device that uses a potassium hydroxide solution to remove the organic combustion product carbon dioxide.

He downplays the role of humus in plant nutrition and has discovered that plants feed on nitrogen compounds and carbon dioxide derived from the air, as well as on minerals in the soil.

One of his most recognized and far-reaching accomplishments is the invention of nitrogen-based fertilizer.

Liebig believes that nitrogen must be supplied to plant roots in the form of ammonia.

Though a practical and commercial failure, his invention of fertilizer recognizes the possibility of substituting chemical fertilizers for natural ones (animal dung, etc.).

He also formulates the Law of the Minimum, stating that the one essential mineral that is in the relatively shortest supply, visualized as “Liebig’s barrel,” limits a plant’s development.

This concept is a qualitative version of the principles used to determine the application of fertilizer in modern agriculture.

Liebig had founded and edited from 1832 the journal Annalen der Chemie, which has become the leading German-language journal of chemistry.

He is also one of the first chemists to organize a laboratory as we know it today.

His novel method of organic analysis makes it possible for him to direct the analytical work of many graduate students.

The vapor condensation device he popularized for his research is still known as a Liebig condenser, although it was in common use long before Liebig's research began.

Liebig's students are from many of the German states as well as Britain and the United States, and they help create an international reputation for their ‘Doktorvater.’

In 1835, Liebig invents a process for silvering that greatly improves the utility of mirrors.

In the same year, he and his student Henri Victor Regnault first produce vinyl chloride, obtaining it by treating ethylene dichloride with a solution of potassium hydroxide in ethanol.

Today an important industrial chemical, it is chiefly used to produce its polymer, polyvinyl chloride (PVC).