The qualitatively different conceptions of 1 mol

Abstract

The present paper arises from a series of studies we have carried out concerning the conceptions of ‘the mole’ held by different actors in the Swedish educational system. It is a report of the results gained in a study with 28 experienced chemistry educators, all of whom were interviewed individually.

A qualitative analysis of the protocols has revealed four separate fundamental meanings of ‘the mole’, described by means of four categories (F_o, F₁, F₂, F₃), complemented by one theoretical fundamental F₄. The fundamentals are incommensurably separated, that is, even if the same words and symbols, such as ‘molar mass’ and ’N_A’, are used in different fundamentals, they have separate connotations. The fundamentals are validated by historical meanings of ‘the mole’.

In the individual educator, the equivocal use of the term ‘mole’ is typical. Every educator has a ‘gravity point conception’ of mole coincident with one of the fundamentals. But, depending on the context, properties belonging to other fundamentals are frequently incorporated, resulting in logical inconsistencies in reasoning, of which the individual is usually unaware.

Our claim is that the fundamentals can be used as tools to make conceptual ambiguities about ‘the mole’ explicit both in individuals and textbooks. They can also be used as starting‐points for descriptions of different teaching models concerning ‘the mole’, as will be shown in a forthcoming article in this journal.