Amedeo Avogadro

Lorenzo Romano Amedeo Carlo Avogadro, Count of Quaregna and Cerreto (, also, Italian: [ameˈdɛːo avoˈɡaːdro]; 9 August 1776 – 9 July 1856) was an Italian scientist, most noted for his contribution to molecular theory now known as Avogadro's law, which states that equal volumes of gases under the same conditions of temperature and pressure will contain equal numbers of molecules. In tribute to him, the ratio of the number of elementary entities (atoms, molecules, ions or other particles) in a substance to its amount of substance (the latter having the unit mole), 6.02214076×1023 mol−1, is known as the Avogadro constant. This constant is denoted NA, and is one of the seven defining constants of the SI.

9 August 1776

Born on the same birth day (9 August): Anna Kendrick • Barton Lynch • Bernhard Schott • David Steinberg • Denis Atkinson • Eric Bana • Erich Hückel • Evelina Haverfield • George Armstrong (footballer) • Jacques Parizeau • Jason Frasor • John E. Sweeney • Kay Stenshjemmet • Li Jiawei • Linn Ullmann • Melanie Griffith • Mikaël Silvestre • Nitin Chandrakant Desai • Patrick Depailler • Stefano Okaka • Tetsuko Kuroyanagi • Victoria Jiménez Kasintseva • Whitney Houston

Born in the same month (August 1776): Thomas Bladen Capel