Louis Pasteur it became best known for its contributions to the pasteurization process (used to destroy pathogenic microorganisms in food). But don't think that the studies of this noble scientist were limited only to this area.
Stereochemistry (the branch of chemistry that studies the spatial arrangements of molecules) took its first steps thanks to Pasteur. The basis of his studies were the salts of tartaric acid formed in wine barrels. The shape of the salt crystals caught the attention of Pasteur, who started to research them under the action of polarized light. The research on the molecular constitution of crystals was the “kick start” for the development of the stereochemical science, in 1848.
Get to know Pasteur's procedure:
The first step was the preparation of an aqueous solution of tartaric acid. Then, the solution was taken for analysis in a polarimeter (an instrument designed to measure the angle of rotation of the plane of polarization of an optically active substance). Pasteur came to the conclusion that the incident light was bent to the right, that is, the components of the mixture were optically active and right-handed.
Pasteur's experiment made it possible to combine crystallography, chemistry and optics. The union of these sciences explains the relationship between the outer shape of a crystal, its molecular constitution and its action under polarized light.
By Líria Alves
Graduated in Chemistry
Source: Brazil School - https://brasilescola.uol.com.br/quimica/estereoquimica-na-visao-louis-pasteur.htm
