Avogadro constant

The Avogadro constant ($N_{A}$) in Le Système international d'unités is given by (Ref. 1):

N_A = 6.02214129 x 10²³ mol^-1

History

The first person to try elucidate an analogous value was Johann Josef Loschmidt in 1866 (Ref. 2). However, this constant was named after Lorenzo Romano Amedeo Carlo Avogadro by Jean Perrin in 1909 (Ref. 3).

Interesting reading

• F. A. Paneth "Avogadro's Number and Loschmidt's Number", Nature 179 p. 145 (1957)
• Ronald Newburgh, Joseph Peidle and Wolfgang Rueckner "Einstein, Perrin, and the reality of atoms: 1905 revisited", American Journal of Physics 74 pp. 478-481 (2006)

References

1. CODATA
2. J. Loschmidt "Zur Grösse der Luftmolecüle", Sitzungsberichte der kaiserlichen Akademie der Wissenschaften zu Wien: Math-Naturwiss., Klasse 2, 52 pp. 395–413 (1866)
3. Jean Perrin "Mouvement brownien et réalité moléculaire", Annales de chimie et de physique XVIII (8e série) pp. 5-113 (1909) Page images on Gallica
4. G. Mana and G. Zosi "The Avogadro constant", La Rivista del Nuovo Cimento 18 pp. 1-23 (1995)