A reconstruction of development of the periodic table based on history and philosophy of science and its implications for general chemistry textbooks

Abstract

The objectives of this study are: (a) elaboration of a history and philosophy of science (HPS) framework based on a reconstruction of the development of the periodic table; (b) formulation of seven criteria based on the framework; and (c) evaluation of 57 freshman college-level general chemistry textbooks with respect to the presentation of the periodic table. The historical reconstruction of the periodic table showed that the periodicity of the elements could be construed as an inductive generalization or as a function of the atomic theory. There is considerable controversy with respect to the nature of Mendeleev's contribution, and various alternatives are discussed: ordered domain; empirical law; and a theory with limited explanatory power. Accommodation of the elements according to their physicochemical properties is considered to be the major contribution of the periodic table by all textbooks, followed by contrapredictions of previously unknown elements (30 textbooks), and novel predictions (corrections of atomic mass) of known elements (10 textbooks). The relative importance of accommodation and prediction within an HPS framework is generally ignored. Few textbooks have attempted to explore the possible cause of periodicity in the table and very few textbooks have explored the nature of Mendeleev's contribution. The development of the periodic table as a sequence of heuristic principles in the form of a convincing argument has been ignored. The textbook approach of emphasizing that the development of the periodic table was an inductive generalization, and that Mendeleev had no model or theory, does not facilitate the spirit of critical inquiry that led the scientists to grapple with alternative interpretations, conflicts, and controversies. It is concluded that the development of the periodic table went through a continual critical appraisal (conflict and controversy), in which scientists presented various tentative theoretical ideas to understand the observed phenomena. ß

Los libros de texto de ciencias como objeto de investigación: una revisión bibliográfica

“…Se enfocan principalmente al producto y no al proceso de la actividad científica, de tal manera que la ciencia pasa a ser una recolección de hechos, no un proceso dinámico de generación y prueba de explicaciones alternativas. El «método experimental» es prácti-camente la única vía para elaborar conocimiento científico válido (Knain, 2001;Malaver et al, 2004;Brito et al, 2005;van Eijck y Roth, 2008;Páez y Niaz, 2008;Serhat, 2009). Se priorizan detalles sin las reconstrucciones históricas de los datos, se omite el contexto, el marco teórico que orienta al científico y las posibles interpretaciones alternativas que pueden dar lugar a conflictos y controversias (Rodríguez y Niaz, 2004a).…”

Do general chemistry textbooks facilitate conceptual understanding?

“…Besides atomic structure, a review of the literature shows that textbooks follow the same approach in many other topics, such as: determination of the elementary electrical charge 14 , kinetic theory 15 , origin of the covalent bond 16 , laws of definite and multiple proportions 17 and the periodic table 18 . It is suggested that chemistry teachers can facilitate greater conceptual understanding by incorporating historical episodes that form part of the curriculum and at the same time illustrate that progress in science inevitably leads to discussions, arguments and controversies.…”

Breaking the law: promoting domain-specificity in chemical education in the context of arguing about the periodic law

“…The Periodic Law seems not to be exact in the same sense as are laws of physics, for instance Newton's laws of motion. How the Periodic Law is particular to chemistry, what it enables chemists to do and how it compares to laws in other domains are questions that can contribute to efforts in refining chemical education so as to improve students' understanding of the Periodic law, given this is a significant goal in chemical education (Brito et al 2005). Schwab (1958), like Hoffmann, had argued that science teaching should nurture themes that characterize a science as a distinct way of knowing.…”