New Perspectives in Science Education

This work arises form the EU History and Philosophy in Science Teaching Project

The activity is relevant to upper secondary school science, and for all abilities.

We advocate a fresh approach to chemical formulae that widens the focus from algorithmic balancing equations and routine calculations. We recommend one that focuses on the endeavours of chemists from the past to lay the quantitative foundations of chemical materials and reactions through the processes of painstaking and careful analytical chemistry, and that recognises the character of formulae and equations as meaningful representations of fundamental chemical processes. We adopt a semiotic (semiotics: the study of signs and symbols, especially as means of language or communication) approach that focuses on the meanings of the components and of the whole of the formulae and equation. To do this, we need to examine the creation of conventions of chemical symbolism, and the role of chemists who made these conventions in history. We also examine ontology, or nature, of the entities that make up formulae and equations. In the case of formulae, the nature of the entities is often implicit, so that whether particles are ions or molecules is often hidden in some formulae. We discuss why there are discrete molecules in some materials but none in others that have a giant structure, for example. In the case of equations, we imagine the value of word equations, against symbolic equations. There is a range of equation types rarely discussed at this level, but whose richness of meaning helps us to delve into the meaning of the chemical processes themselves. We do not lose sight of the calculations altogether, since they represent a secondary importance of the equations, but rather adopt a critical stance that sees calculations as applying to ideal situations, but not quite real life where the equations only approximate to the concrete position.

The outcomes are more than a deeper understanding of formulae and equations themselves, but a more general view of the significance of conventions and symbolism in this part of chemistry. A sceptical approach to realism is also an important aim of this topic.