Birth of Amedeo Avogadro

Amedeo Avogadro was born on 9 August 1776 in Turin. An Italian scientist, Avogadro trained as a lawyer before turning to physics and chemistry and becoming a professor at Turin. In 1811 he proposed that equal volumes of gases at the same temperature and pressure contain the same number of molecules, an idea that helped to resolve confusion about atoms and molecules and the determination of atomic weights. His hypothesis was largely neglected for decades, until Stanislao Cannizzaro revived it at the Karlsruhe Congress in 1860. The Avogadro constant, which gives the number of particles in a mole of a substance, was named in his honor.

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