https://doi.org/10.1351/goldbook.A00543

The Avogadro constant, N_{A} = 6.022 140 76 x 10^{23} mol^{-1}, is a proportionality constant between the quantity amount of substance (*n*, with unit mole) and the quantity for counting entities (*N* with unit one, symbol 1), *N* = *N*_{A}*n*.**Notes: **

*Sources: *

BIPM, Le Système international d’unités (SI), SI Brochure, 9^{e} ed. (2019), p. 17 (https://www.bipm.org/fr/publications/si-brochure/)

BIPM, The International System of Units, SI Brochure, 9^{th} ed. (2019), p. 129 (https://www.bipm.org/en/publications/si-brochure/)

Green Book, 3^{rd} ed. (https://doi.org/10.1039/9781847557889)

- In the revision of the International System of Units (SI) of 2019 the Avogadro constant became one of the seven defining constants with the exact value 6.022 140 76 x 10
^{23}mol^{-1}. - The Avogadro number is the exact numerical value of the Avogadro constant, 6.022 140 76 x 10
^{23} - While the symbol
*N*_{A}is used to honour Amedeo Avogadro, the symbol*L*is used in honour of Josef Loschmidt.

BIPM, Le Système international d’unités (SI), SI Brochure, 9

BIPM, The International System of Units, SI Brochure, 9

Green Book, 3