Relationships between everyday knowledge and scientific knowledge: understanding how matter changes

Abstract

This paper analyses the representations held by adolescents and university students in relation to the mechanism for explaining changes in matter (changes of state, dissolutions, expansions and chemical reactions) in terms of the kinetic theory. The answers to a questionnaire were analysed by considering the proportion of correct answers and the use of alternative conceptions. The results show that understanding of explanatory mechanisms of changes in matter is affected by age and instruction level and content of the problem. The main conception that competes with the kinetic model is the attribution to the particles of the changes observed, at a macroscopic level. This is more evident in changes of state and expansions than in other changes. This confusion results from a failure to differentiate properly between the represented reality and the model that represents it. In conclusion, analysis has shown once more students' difficulties in going beyond apparent reality or integrating the data obtained from it into the scientific models they learn at school.

Acknowledgements

The present work is part of the Research Project BSO2002‐01557, granted by the Ministerio de Ciencia y Tecnología of Spain, supervised by the second author. The authors thank María Sagrario Gutiérrez for her comments and Antonio Pardo for his statistical advice.

Notes

We compare these pairs of categories with the t proof, at the same level of confidence used in previous ANOVAs (p < 0.001), in order to make easier the comparisons.