Accreditation and Quality Assurance

, Volume 19, Issue 3, pp 213–220 | Cite as

The mole is an Avogadro number of entities, the macroscopic unit for chemical amount

  • B. P. Leonard
Discussion Forum


Just as the gram is an Avogadro number of daltons, g = (g/Da) Da, the current definition of the mole can be interpreted as an Avogadro number of entities, as it is often thought of by chemists—and it should be explicitly redefined this way. By introducing a hitherto missing atomic-scale unit for the amount of any substance, the entity (symbol ent), analogous to the dalton for mass, we can then define the mole as: mol = (g/Da) ent—i.e., an Avogadro number of entities. It is argued that the name for the base quantity should be “chemical amount,” by analogy with “electric current.” Recent proposals and counterproposals for redefining the mole (and renaming “amount of substance”) are critically discussed in light of the above intuitively obvious definition.


Redefinition of mole Avogadro number Avogadro constant Entity New SI Chemical amount Amount of substance Number of entities 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.The University of AkronAkronUSA

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