Fuels and Combustion: Definitions and Specifications for Didactic Transposition and Outreach Purposes

Abstract

Starting from a literature inspection, an examination of the definitions of fuel and combustion found for educational and outreach purposes is conducted. In many textbooks, handbooks, slides, or websites that disseminate scientific topics, the definition of fuel (as a product) and of combustion (as a process) is skipped to give room to practical aspects such as classification and technical performances of fuels. Anyway, many unsatisfactory definitions of fuels and combustion are available, full of omissions, imprecisions, ambiguities, and even outright errors. The definition of combustion is often lacking and favours thermodynamic aspects while neglecting kinetic ones, as if it were disconnected from practice and phenomenal reality as it is understood today. The critical examination of the current teaching approach on fuels and combustionwith particular attention to the high school and university levels, allows us to identify weaknesses and to propose new definitions more suitable to avoid grey areas of the lessons. It is also proposed to refine the definition of fuel by considering the inclusion of nuclear fuel and taking into account the humongous difference between a chemical decomposition and an atomic transmutation. With respect to metals as fuels, a comparison between burning and rusting of iron is also examined.
This is a fundamental topic of industrial chemistry, the teaching of which is based on a broad set of prerequisites and, in general, a good knowledge of basic chemistry. The subject of fuels and combustion is of interest to students in high schools (even if the educational path on fuels and energy can start with some rudiments from primary school) and universities, due to its obvious relationships with energy production systems, mobility, and everyday life. Fuels and related subjects can be an excellent theme to motivate students to study chemistry and applied chemistry. The importance of language and terminology in brain-based lesson planning is also discussed, considering the language as the barycentre of teaching/learning.