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Georgios
TSAPARLIS
EXCERPTS: … For many, chemistry is the experimental science. It emerged first as a craftsmanship, the metallurgy of ancient Greek chymeutae. A theoretical/philosophical quest was initiated at about the same time by ancient Greek philosophers… The ideas of Leucippus and Democritus were indeed the foundation of modern science. On the other hand, (according to Niaz), "although experimental details are important, the theoretical rationale in which the experiment is conducted, is even more important". …
This issue of CERAPIE deals with the structural theories and
the role they play in the teaching and learning of chemistry…Contributions
were invited that cover three distinct areas: science, science education,
history and philosophy of science. Distinguished scientists/chemical
educators and science education researchers have contributed their expertise.
I thank all contributors to this theme issue. Note that … a second
issue on the same theme is planned for the May 2002 issue (see relevant
CALL FOR PAPERS in this issue for deadlines and conditions). Ronald J. Gillespie with Cherif F. Matta draw attention to a number of features of the VSEPR model, (and) discuss the relationship of the model to the electron density. … The fundamental basis for the VSEPR model is provided by the Pauli principle and not by electrostatics… (You may be) surprise(d) to realise that free atoms or monoatomic ions with an octet of electrons in their valence shells (such as Ne, F-, O2-) do not have four electron pairs (as commonly depicted), but instead electrons move freely around the corresponding nucleus, giving a spherical total electron density. In quantum-chemical terms, this is a result of electron correlation… Frank Weinhold and Clark R. Landis discuss natural bond orbitals (NBOs) that are close to our traditional concept of bonding and valence as pioneered by Lewis.. The latest version of a computer program (NBO 5.0) makes feasible the computation of NBOs with related applications for systems of practical interest. Of great interest is the discussion about extending the localised bonding concepts to transition metals… For d-block elements, the authors derive the so-called "Rule of 12" (dodectet rule), which is analogous to the famous "Rule of 8" (octet rule). Sidney F. Kettle questions the division of chemistry into the traditional branches of inorganic, organic and physical, (and) discusses the role that structure is called to play in future inorganic chemistry. It is hoped that the special role of structure in organic chemistry … will be dealt with in the second theme issue of CERAPIE which is planned for May 2002. Biochemistry and molecular biology play (an important role) in modern science. Central here is biomolecular structure as related to biological function. David R. Canning and James R. Cox state that "understanding the three-dimensional nature of the structural elements of proteins (for instance) is essential if students are to understand how proteins fold into thermodynamically favorable structures and form biologically relevant complexes"…. (They further) provide information about available tools for the molecular visualisation of biological molecules. Keith S. Taber has compiled a review of educational research into the structural concepts of chemistry… The reading of this review paper is a must for every science-education researcher as well for teachers of chemistry. Of special interest is the proposed alternative chemical ontology, in which the focus is not on atoms but on molecules and ions… Most real chemistry involves molecules, or ions, or more extensive systems, while discrete atoms are seldom featured in significant chemical processes. (In) contrast, the atom has a privileged place in the (current) teaching and learning of chemistry. Mansoor Niaz and Maria A. Rodriguez (maintain that) "various topics of the general chemistry program, at both the high school and freshman level, can be presented within a history and philosophy of science perspective"… Niaz's studies (on) 'rational reconstructions' of various structural theories (are reviewed). (Topics studied were) the cathode ray, alpha particle, the oil drop experiments, the origin of the kinetic theory and of the covalent bond, and the law of multiple proportions. The authors conclude by stating that "history and philosophy of science is already 'inside' chemistry and this perspective can facilitate students' conceptual understanding". A central issue in chemistry teaching is the role of physics in chemistry. The question arose as to whether chemistry could be reduced to physics. Eric Scerri has contributed greatly to the question of reductionism in chemistry, and… in this Issue, (he) discusses the new philosophy of chemistry and its relation to chemical education, with special emphasis on quantum chemistry. …
Teaching and learning about atoms and molecules is a heavy task for
both teachers and pupils… Despite the calls from science-education
researchers, chemistry textbooks continue the practice of treating too
much abstract material at an elementary physical chemistry level. Leading
chemical educators such as Ron Gillespie have put forward views and
suggestions that may help surpass the above deadlock.… (According
to him) central is the need continually to emphasise the relationship
between observations and atoms and molecules.
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