ABSTRACT
Acidity is often associated with food. Indeed, the name acidity comes from the Latin “acetum” that, together with wine, gives the famous Latin phrase “vinum acetum” which can be translated as “wine turned sour” or vinegar. During the 19th century, chemists start to experiment by mixing metals with organic compounds. They find that many metals lead to practical difficulties. In 1922, Hans Meerwein makes a suggestion that changes the field of organic chemistry. He understands that carbocations can play the role of intermediates during a chemical reaction. The presence of a carbocation as a reaction intermediate has an important consequence for the properties of the products, specifically, for a property known as optical activity or chirality. In the second half of the 19th century, chemists start to realize that the rate of chemical reactions depends not only on the reactants, but also the medium, or solvent, in which reactions are carried out.
