Foundations of Chemistry最新文献

This paper establishes that Robert Boyle’s complex chemical ontology implies a non-reductionistic conception of chemical qualities and, more specifically, a conception of chemical qualities as being dispositional and relational. Though Peter Anstey has already shown that that Boyle considered sensible qualities to be dispositional and relational, this moves beyond Anstey’s work by extending his arguments to chemical properties. These arguments are, however, merely a first step in establishing a non-reductionistic interpretation of Boyle’s chemical ontology. A further argument will show that Boyle regards chemical and other higher-level properties as being emergent and supervenient properties. These arguments are supported by substantial textual evidence from Boyle’s writings, which show that he clearly conceived of chemical substances as functional wholes whose properties emerge not only from the microstructural ordering of their parts but also from their relationship with other chemical substances within the context of experimental practice.

For a period of several years the philosopher of science Hasok Chang has promoted various inter-related views including pluralism, pragmatism, and an associated view of natural kinds. He has also argued for what he calls the persistence of everyday terms in the scientific view. Chang claims that terms like phlogiston were never truly abandoned but became transformed into different concepts that remain useful. On the other hand, Chang argues that some scientific terms such as acidity have suffered a form of “rupture”, especially in the case of the modern Lewis definition of acids. Chang also complains that the degree of acidity of a Lewis acid cannot be measured using a pH meter and seems to regard this as a serious problem. The present paper examines some of these views, especially what Chang claims to be a rupture in the definition of acidity. It is suggested that there has been no such rupture but a genuine generalization, on moving from the Brønsted-Lowry theory to the Lewis theory of acidity. It will be shown how the quantification and measurement of Lewis acidity can easily be realized through the use of equilibrium theory and the use of stability constants.

An Aristotelian philosophy of nature offers an alternative to reduction for the conception of the inter-theoretical relationships between molecular chemistry and quantum mechanics. A basic ingredient for such an approach is an ontology of fundamental causal powers, and this work aims to develop such an ontology by drawing on quantum-chemical entities, particularly, the electron density. This notion is central to the Quantum Theory of Atoms in Molecules, a theory of molecular structure developed by Richard F. W. Bader, which describes molecules and atoms in terms precisely of the electron density. Then, by identifying a philosophical tension in Bader’s discourse about the nature of electron density, the work will analyze this central notion in terms of the categorical/dispositional distinction regarding properties. The central idea is that electron density can be conceived as categorical and dispositional at once, and this very characterization can avoid Bader’s philosophical tension.

The ideas of quantum simulation and advances in quantum algorithms to solve quantum chemistry problems have been discussed. Theoretical proposals and experimental investigations both have been studied to gauge the extent to which quantum computation has been applied to solve quantum chemical problems till date. The distinctive features and limitations of the application of quantum simulation on chemical systems and current approaches to define and improve upon standard quantum algorithms have been studied in detail. The possibility and consequences of designing an efficient quantum computer that can address chemical problems have been assessed. The experimental realization of quantum supremacy defies the conventional belief of chemists, that millions of qubits would be required to solve fundamental chemistry problems. It is predicted that quantum simulation of quantum chemistry problems will radically revolutionize this field.

Chemistry educator Alex H. Johnstone is perhaps best known for his insight that chemistry is best explained using macroscopic, submicroscopic, and symbolic perspectives. But in his writings, he stressed a broader thesis, namely that teaching should be guided by scientific research on how the brain learns: cognitive science. Since Johnstone’s retirement, science’s understanding of learning has progressed rapidly. A surprising discovery has been when solving chemistry problems of any complexity, reasoning does not work: students must apply very-well-memorized facts and algorithms. Following Johnstone’s advice, we review recent discoveries of cognitive science research. Instructional strategies are recommended that cognitive studies have shown help students learn chemistry.

This paper describes the construction of the Periodic Tables for cations of all elements with charges + 1, + 2, + 3 and anions with charge − 1. The Table for cations⁺¹ differs significantly from other newly constructed Tables and from known Tables, as the d- and f-blocks are inserted into s-block and split it up for two parts. Importantly, a new type of 3d- and 4f-shell contractions has been discovered. The manifestations of secondary periodicity in case of anions is absent or opposite to the manifestations observed for atoms and cations. For kainosymmetric anions, the ionization energies are lowered, which contradicts the theoretical assumptions and experimental data supporting the classical concept of kainosymmetry. Simple formulas are proposed for quantitative description of the manifestations of internal periodicity and kainosymmetry. The regularities of change in these manifestations depending on the charge and the position of ions or atoms in the Periodic Table are established. In the 6th period, the bifurcation in the properties characteristic of the internal periodicity does not occur at usual position, i.e. in the middle of the row from the block of the Periodic Table (p³–p⁴), but takes place earlier, along with the transition of the electronic configurations p²–p³. In other words, the place of transition from "early" to "late" elements changes.

This paper was inspired by the author’s fortunate acquisition of a copy of an original copy of “Muspratt’s Chemistry” that was published in 1860. This raised, for the author, interesting and significant issues regarding the chemistry content and its presentation in the context of chemistry and education today. The paper is presented in two parts: Part 1 explores the content, structure and gives reactions to and insights into the original publication, whereas Part 2 provides a focus on the developments in chemistry education as experienced by the author during almost 70 years of learning and teaching chemistry in schools and in teacher education in England. James Sheridan Muspratt (1821–1871) is best remembered for this publication which is fully entitled “Chemistry, theoretical, practical and analytical as applied and relating to Arts and Manufactures”. This was developed during the period 1852–1860 and ran into several editions as well as being translated into German and Russian. Earlier he had done chemistry research with Liebig and Hofmann, and in 1848 he founded the Liverpool College of Chemistry. It is clear that he corresponded extensively with many of the leading nineteenth century chemists in the UK and Europe, many of whose names are still familiar with us today.

Application of Einstein special theory of relativity in chemistry seems to be superfluous; energies are too low. The average velocity of electron in hydrogen atom (1 s 1) is 1/135 c, making its actual mass only 26,6 ppm bigger than the rest mass. However, for heavier elements (about Z > 60) relativistic effects have to be taken into account and, more, many phenomena cannot be explained without ascribing new mass to electrons, in accordance with Einstein theory. In this paper such phenomena are described: color of metallic gold and Bi and Pb compounds, contraction of Ln-X bond of lanthanide trihalides, voltage of lead-acid and Zn/HgO battery, and the shape of gold clusters. Besides, essentials of Einstein theory and quantum chemistry were problems concerning the validity of Lavoisier law.