If organic branch of the Kazan School of Chemistry comes from N.Zinin, Karl Klauss is a founder of inorganic trend of its development. He made a great contribution to the world science. In 1844, while researching platinum ore from the Ural mines, Klauss discovered a new element - ruthenium. This is the only one among natural elements, opened in Russia and named after the state (as Ruthenia is the Latin for Russia). Preparations of ruthenium and other originals of the elements from platinum group, obtained by Klauss, are kept in the museum.

A great merit of Zinin and Klaus to Russian Chemistry is that, being enthusiastic and very keen on the science, they attracted a lot of talented young people. The most talented one Alexander M. Butlerov was fated to play a great role in the history of the Kazan School of Chemistry and give it his name later on.

For twenty years, from 1849 to 1869, Butlerov worked in the Kazan University. He became a professor at the age of 29. It was in Kazan, where he wrote all his fundamental works, including the theory of chemical structure of organic compounds (1861), which connected chemical properties and molecular structure.

The theory is of great importance: it opened the ways of chemical structure learning and showed chemists methods for different organic molecules' constructing in theory and then in practice. Butlerov made series of purposeful synthesis for his theory to be proved, getting for the first time a number of substances, namely trimethyl-carbone and isobutylene. For the first time he synthesized saccharine substance - "methylenitan" in the laboratory. Many of substances, obtained by Butlerov, are also kept in the museum.

During the period from 1861 to 1863 Butlerov was twice appointed to the post of rector, for the third time he was elected by the University Council, but left the post of his own accord.