Lorenzo Romano Amedeo Carlo Avogadro
Count of Quaregna and Cerreto


  An Italian chemist, in 1820 he became a professor of physics in Turin. During his stay in Vercelli he wrote a concise note (memoria) in which he declared the hypothesis of what we now call Avagadro’s law:

..."equal volumes of gases, at the same temperature and pressure, contain the same number of molecules"...

He is most noted for his contributions to the theory of molarity and molecular weight. As a tribute to him, the number of elementary entities (atoms, molecules, ions or other particles) in one mole of a substance, 6.02x1023, is known as Avogadro’s Number.



  1. "The Road to Karlsruhe" article in the Hexagon of Alpha Chi Sigma

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