(August 9, 1776 – July 9, 1856)
Amedeo Avogadro died exactly a month before his 80th birthday, which was also a day before Nikola Tesla was born. Like some great scientists before him, this physics professor studied religion and law before opting for science. And just like his compatriot, Alessandro Volta, who cashed-in on what eluded Luigi Galvani, Avogadro explored facts which Joseph Louis Gay-Lussac overlooked, alongside those that stumped John Dalton. This resulted in his contributions to Molecular Theory. His famous law (sometimes called hypothesis) propelled Physics and Chemistry to loftier heights. This is noteworthy because during his era the terms “atom” and “molecule” were used interchangeably. Avogadro was indeed the person who fostered the term “molecule”. His works were so ahead of their time that his contemporaries paid no attention to them. Nonetheless, they ushered-in our contemporary era of Particle Physics. It was after André-Marie Ampère rediscovered few of them, that scientists gave them second thoughts. Organic Chemistry experiments, which Auguste Laurent and Charles-Frédéric Gerhardt later conducted, supported Avogadro’s claim that (at constant temperature and pressure) equal volumes of all gases contain equal numbers of molecules. However, he was already dead in 1860 when Stanislao Cannizzaro reenacted and detailed the greatness of his research. They not only helped determine atomic and molecular masses, but effectively reconciled Dalton’s and Gay-Lussac’s postulations. Several years would elapse before his accomplishments’ depths were fully appreciated: and they consolidated his status as a founder of Molecular Theory. The Avogadro lunar crater and the Avogadrite mineral are dedicated to him.