The mole is not an ordinary measurement unit

  • Ingvar Johansson
Discussion Forum


In this paper, it is argued that the SI system has not carefully enough taken into account the differences that exist between stoichiometry and physics, and because of this neglect forced the kind-of-quantity amount of substance into a false form. The mole is not a unit such as the metre, the kilogram, and the second. It is a “unit” only in the sense in which purely mathematical scaling factors can be called units.


Mole SI system Avogadro number Avogadro constant Stoichiometry 



The paper owes much to the straightforward discussions that have taken place in a couple of small mailing groups where I am lucky to have become adopted. In particular, I am grateful to Paul De Bièvre, Walter Emerson, Marcus Foster, Stephen Humphry, Brian Leonard, and Gary Price. I thank De Bièvre for the invitation to write this paper.


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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  1. 1.Umeå UniversityLundSweden

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