number of entities, \(N\)

https://doi.org/10.1351/goldbook.N04266
Integer number obtained by counting of entities, which are usually molecules atoms or ions.
Sources:
Green Book,2nd ed., p. 39 (https://www.cintegrado.com.br/site/documentos/green_book_2ed.pdf)
PAC, 1996, 68, 957. 'Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)' on page 985 (https://doi.org/10.1351/pac199668040957)