https://doi.org/10.1351/goldbook.A00543
The Avogadro constant, \(N_{\text{A}} = 6.022\ 140\ 76 \times 10^{23}\ \text{mol}^{-1}\), is a proportionality constant between the quantity @A00297@ (\(n\), with unit mole) and the quantity for counting @N04266@ (\(N\) with unit one, symbol 1), \(N = N_{\text{A}}\ n\).
Notes:
- 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 \(6.022\ 140\ 76 \times 10^{23}\ \text{mol}^{-1}\).
- The Avogadro number is the exact numerical value of the Avogadro constant, \(6.022\ 140\ 76 \times 10^{23}\)
- While the symbol \(N_{\text{A}}\) is used to honour Amedeo Avogadro, the symbol \(L\) is used in honour of Josef Loschmidt.