Philosophy of Chemistry

Book Review Zaterka, Luciana and Mocellin, Ronei Clécio. Ensaios de História e Filosofia da Química. São Paulo: Editora Ideias e Letras, 2022, 328 p. ISBN 978-658729531-2.

The article begins with a response to a recent contribution by Jensen, in which he has criticized several aspects of the use of triads of elements, including Döbereiner’s original introduction of the concept and the modern use of atomic number triads by some authors including myself. Such triads are groups of three elements, one of which has approximately the average atomic weight of the other two elements, as well as having intermediate chemical reactivity. I also examine Jensen’s attempted reconstruction Mendeleev’s (...) use of triads in predicting the atomic weights of three hitherto unknown elements, that were subsequently named gallium, germanium and scandium. The present article then considers the use of atomic number triads, in conjunction with the phenomenon of first member anomaly, in order to offer support for Janet’s left-step periodic table, in which helium is relocated into group 2 of the table. Such a table features triads in which the 2nd and third elements of each group, without fail, fall into periods of equal length, a feature that is absent in the conventional 18-column or the conventional 32-column table. The dual sense of the term element, which is the source of much discussion in the philosophy of chemistry, is alluded to in further support of such a relocation of helium that may at first appear to contradict chemical intuition. (shrink)

‘Structure’ is the term whose proper use is exemplified by an expression like ‘the structure of a diesel-engine,’ in which what is referred to is accessible to immediate observation. It is also used figuratively like ‘social structure.’ While unobservable, what is referred to is empirically accessible. By contrast, molecules are neither observable nor empirically accessible. What philosophical grounds enable us to design invisible structure of molecules? Our cognition of objects becomes realized as phenomena when objects are given to our phenomenal (...) fields. A phenomenal field is a pictorial representation of the mind’s self-transcending character and shows the relation between ‘self’ and ‘world.’ Molecular structure becomes realized as an affordance of molecules in a phenomenal field proper to organic chemists. It is a context-sensitive dispositional attribute of an {organic chemist-world} complex. Although designing molecules presupposes molecular structure, the latter is not sufficient for the former to make sense. Molecules must be designable as well. Designing molecules aims to create or modify molecular structure in order to provide compounds with certain chemical and/or physical properties. That is, designable molecules make sense in contexts in which they serve as a means to achieve this purpose and become realized as an affordance. Given that molecular structure and designable molecules are affordances of molecules, the fact that there are contexts in which they make sense provides grounds for conceiving and designing invisible structure of molecules. Heidegger’s arguments in Being and Time about characteristics of the being of beings corroborate our argument that what becomes realized as an affordance exists as what he calls a useful thing for us. (shrink)

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. (shrink)

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. (shrink)

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. (shrink)

Teaching chemistry remains a profoundly challenging activity. This paper arises from reflection on the challenges of creating meaningful assessments. Herein a simple framework to assist in making more visible the different kinds of knowledge required for mastery of chemistry is described. Building from a realist foundation the purpose of this paper is to lay the intellectual scaffolding for the framework. By situating the framework theoretically, it is intended to highlight the value of engaging with philosophy for the project of knowledge (...) building in chemistry. Use of this framework has laid bare some significant limitations to the ways in which organic chemistry has been assessed. Making the visible to students aids in their engagement with knowledge and for a small minority has developed their understanding of science more generally. The framework provides a simple, easily usable tool for the evaluation of chemistry assessments. (shrink)

We re-examine the history of the element “nipponium” discovered by a Japanese chemist Masataka Ogawa in 1908. Since 1996 H.K. Yoshihara has made extensive research into Ogawa’s work and revealed evidence that nipponium proposed for the place of the atomic number of 43 was actually rhenium. In this paper, we provide critical re-interpretations of the existing information and confirmed that Ogawa left indisputable evidence that nipponium was in fact rhenium. We further discuss the reasons for the existing doubts and criticism (...) against Ogawa’s discovery and Yoshihara’s interpretation, and attempt to resolve them. (shrink)

We review the early works which were precursors of the Conceptual Density Functional Theory. Starting from Thomas–Fermi approximation and from the exact formulation of Density Functional Theory by Hohenberg and Kohn’s theorem, we will introduce electronegativity and the theory of hard and soft acids and bases. We will also present a general introduction to the Fukui functions, and their relation with nucleophilicity and electrophilicity, with an emphasis towards the importance of these concepts for chemical reactivity.

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 is 1/135 c, making its actual mass only 26,6 ppm bigger than the rest mass. However, for heavier elements 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. (shrink)

Eric Scerri is the world-leading expert on Periodic Table and was quite recently named the second-most influential academic in the field of chemistry over the last decade by Academic Influence. In this interview we discuss his main questions of interest in the philosophy of chemistry—the question of reduction of chemistry to physics and the dual sense of chemical element—in the context of his main study object, the periodic table of elements. Among other things, we touch upon the more specific issues (...) related to chemical classification, such as pair reversal, the placement and order of certain elements, the structure and shape of periodic table, etc. We also discuss the status of chemical kinds as a traditional epitome of ‘natural kinds’, the relevance of philosophy of chemistry for chemical science, the implications of ‘turn to practice’ for philosophy of chemistry, and many other issues. Finally, Eric Scerri also discusses his most recent book, ‘What is a Chemical Element?’, co-edited with Elena Ghibaudi and published by Oxford University Press in 2020. (shrink)

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 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. (shrink)

This manuscript explores the orthogonality constraints on configurations and orbitals subject to the property that states are mutually orthogonal. The orthogonality constraints lead to properties that affect the description of chemical systems. When states are described as linear combinations of configurations, the coefficient matrix diagonalises S−1H. Therefore, single-configuration states are only possible in one-electron systems: non-orthogonal configurations yield single-configuration states only if S−1H is diagonal, but this would violate the orthonormalisation constraint. Further, the coefficient matrix is not constrained to be (...) square. Similarly, the orbitals used to construct configurations may also be orthogonal or non-orthogonal; orbitals are only required to be mutually orthogonal at the one-electron limit. Orthogonal orbitals are generally preferred due to their mathematical and conceptual simplicity, leading to fictitious unoccupied orbitals. Since the Fock operator is orthogonality agnostic, non-orthogonal orbitals can be generated by solving the Fock equation independently for each electron; the virtual orbitals produced by this conception are true excitation orbitals as they are eigensolutions of the Fock operator. Additionally, we show that the number of molecular orbitals generated is not restricted to the number of atomic orbitals employed in the computation. This manuscript explores the mathematical relationships that need to be satisfied under the various orthogonality regimes. We also present mathematical relationships that provide results that are independent of the orthogonality approximation within a particular computational method. (shrink)

A new way of understanding entropy as a macroscopic property is presented. This is based on the fact that heat flows from a hot body to a cold one even when the hot one is smaller and has less energy. A quantity that determines the direction of flow is shown to be the increment of heat gained divided by the absolute temperature. The same quantity is shown to determine the direction of other processes taking place in isolated systems provided that (...) q is determined by the state of the system. Entropy emerges as the potent energy of a system [Σ], the potency being determined by 1/T. This is shown to tie in with the statistical mechanical interpretation of entropy. The treatment is shorter than the traditional one based on heat engines. (shrink)

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. (shrink)

Faith, War, and Violence analyzes the age-old links between religion and violence perpetrated in the name of God, and the role religion performs in politically infusing the state with romantic spiritualism. The volume examines instances of this phenomenon from ancient Rome to the modern day; it finds that religion-inspired violence is not restricted to Abrahamic faiths or to one geographic region. The fact that symbolically charged religious violence has destructive consequences is not lost on contributors to Faith, War, and Violence. (...) Among the subjects tackled are: the ideological and religious foundations that inspired the founders of Al-Qaeda and its role in the Arab Spring; the long history of religious conflict in Ireland known as the Troubles; Sikh extremism; and the evolution of the Christian approach to war. As the contributors demonstrate, in Western societies, the unity of religious fervor and warmongering stretches from Constantine's incorporation of Christian symbols into Roman army flags to slogans like Gott mit uns, which appeared on the belt buckles of German soldiers in World War I. In recent years, George W. Bush declared the war on terror a "crusade," and his speechwriter, David Frum, coined the religiously inspired term "Axis of Evil," to describe Iraq and other countries opposing the United States. (shrink)

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, 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. (shrink)

Modern science generally assumes that the same laws of logic apply to mechanical, chemical and biological entities alike because they are all ultimately material objects. This may seem to be so obvious that there would be no need to validate it -- experimentally or logically. In this article we would like to critically examine this assumption and show that from an experiential/observational level, as well as from a rational/logical level, it is not valid. This becomes apparent, for instance, when we (...) consider the simple observation in which we distinguish animate from inanimate objects: those objects that seem to spontaneously move themselves and those that move only when impelled by some applied force outside or beyond the object. This distinction may be valid at the macroscopic level more than at the level of theoretical atomic particles. Thus the detailed nature of spontaneous movement must also be understood. (shrink)

It is a notion commonly acknowledged that in his work Timaeus the Athenian philosopher Plato laid down an early chemical theory of the creation, structure and phenomena of the universe. There is much truth in this acknowledgement because Plato’s “chemistry” gives a description of the material world in mathematical terms, an approach that marks an outstanding advancement over cosmologic doctrines put forward by his predecessors, and which was very influential on western culture for many centuries. In the present article, I (...) discuss inter-transformations among Plato’s four types as well as the interpretation they received in the literature. I find that scientists and scholars generally emphasized mathematical aspects of these “reactions” over the philosophical ones. I argue that Plato’s “chemistry” in fact bears on crucial topics of his philosophical system, such as Forms, Becoming, causation and teleology. I propose that consideration of these doctrines help to understand not only the sense of his “chemical” reactions, but also the reason why their stoichiometry is by surface balance and is restricted only to types that come to be and pass away but not to those that provoke the inter-transformations. (shrink)

The concept of substance is considered fundamental in order to understand chemistry and other related concepts, but many problems have been reported about its learning process. Considering the importance of textbooks in the training of chemistry teachers, this study aimed to identify the concepts of substance in general chemistry textbook glossaries. In addition, the study assessed the concepts of substance in relation to other chemical concepts and, when available, compared them with the concepts established by the IUPAC. The methodology employed (...) was content analysis and the results showed that concepts and statements related to the term ‘substance’ are different in the general chemistry textbooks analyzed. They also differ from those stated by IUPAC. Furthermore, it was found that many concepts are dependent on the concept of substance. It is concluded that there must be a greater effort from the community of chemists and the teaching of chemistry in the search for conceptual uniformity to reduce the problems of conceptual understanding. (shrink)

Dans son article The Ground between the Gaps, Jonathan Shaffer développe une conception de l'explication métaphysique impliquant les notions de fondation et de loi métaphysique. Je soutiens ici qu'une telle conception se révèle inadéquate pour saisir les explications métaphysiques courantes des sciences empiriques. Ma démarche consiste à appliquer le cadre théorique de Schaffer à certains types d'explication de la chimie. Bien qu'il soit possible de dégager des lois métaphysiques en chimie, une codification de celles-ci se révèle toutefois impossible. Il y (...) a fort à parier que ce résultat est généralisable à l'ensemble des sciences empiriques. Au strict minimum, cela indique que la conception de l'explication métaphysique de Schaffer doit être révisée. (shrink)

After the birth of thermodynamics’ second principle—outlined in Carnot's Réflexions sur la puissance motrice du feu —several studies provided new arguments in the field. Mainly, they concerned the thermodynamics’ first principle—including energy conceptualisation—, the analytical aspects of the heat propagation, the statistical aspects of the mechanical theory of heat. In other words, the second half of nineteenth century was marked by an intense interdisciplinary research activity between physics and chemistry: new disciplines applied to the heat developed in the form of (...) analytical, mechanical and statistical theories. Inside all these theories, entropy—the brand-new function that Clausius coined in his Mechanical theory of heat—started to play a central epistemic role. In the present paper, we analyse some steps of the historical process of conceptualisation of such function from 1850 to 1902. Particularly, we retrace the historical–foundational path that—starting from Clausius’ Second Law—lead Boltzmann and Gibbs to their distinguished formulations of statistical entropy. As usual, our research has been unrolled through the analyses of primary sources and by leaning on critical readings of the secondary literature. As for the methodological approach, text analysis of historical documents constituted our privileged modus operandi. This paper is the expression of a collaborative historical research program focused on the thermodynamic foundations of physics–chemistry relationship; early results have already been published by the same authors upon the concepts of reversibility––and––thermal equilibrium. (shrink)

In a recent article entitled “The problem of molecular structure just is the measurement problem”, Alexander Franklin and Vanessa Seifert argue that insofar as the quantum measurement problem is solved, the problems of molecular structure are resolved as well. The purpose of the present article is to show that such a claim is too optimistic. Although the solution of the quantum measurement problem is relevant to how the problem of molecular structure is faced, such a solution is not sufficient to (...) account for the structure of molecules as understood in the field of chemistry. (shrink)

No exact definition of an “organic” substance has been agreed upon by the chemical community and textbook definitions vary substantially. The question of what exactly constitutes an “organic” substance is explored in this paper. Various carbon-containing substances that have been by some considered to be “inorganic” are examined in an attempt to ascertain whether carbon in these compounds display different chemical behavior than what is expected of carbon in an “organic” substance. Types of substances considered are carbon allotropes, carbides, carbonates (...) and bicarbonates, cyanide and cyanate ions, carbido clusters, carbon oxides, and compounds without hydrogen.Graphic abstract. (shrink)

A simple treatment of chemical equilibrium is given, based on Boltzmann’s distribution law. The results are compared with those obtained by using thermodynamics.

The objective of the present review on the evolution of Green Chemistry, since its emergence until 2016, aimed an integrated vision of its progress along the three phases of its development: emergence, divulgation and consolidation. The methodology involved the analysis of a selection of bibliography on the evolution of GC collected from issues of the ACS symposia series; editorials in specialized GC journals; and commemorative birthday papers/editorials of these journals and of the GC itself. The analysis allowed to identify and (...) discuss the characteristics and conceptions of GC agents about fundamental concepts and procedures, in order to visualize and better understand the state of knowledge and the subject areas that make up the field. The main alterations identified in the evolution of GC were: it acquired a better defined identity, with more participation of academy and increased scope; was progressively framed in sustainability; has been aspiring to a holistic frame and to a change on the nature of the innovation for its implementation, from incremental to transformative. The analysis suggests that for supporting expansion and consolidation of GC the following aspects deserve attention: full validation of chemical greenness by metrics; better characterization of the frontiers of GC research areas/themes; increased integration between academy and industry; and penetration in chemistry curricula. Its basic philosophy being the practice of a chemistry more focused on the environment preservation, GC means a new stage in nature and in the history of Chemistry. (shrink)

The periodic table is one of the best-known systems of classification in science. Because of the information it contains, it raises explanation-seeking questions. Quantum mechanical models of the behaviour of electrons may be seen as providing explanations in response to these questions. In this paper we first address the question ‘Do quantum mechanical models of atoms provide legitimate explanations?’ Because our answer is positive, our next question is ‘Are the explanations provided by quantum mechanical models of atoms mechanistic explanations?’. This (...) question is motivated by the fact that in many scientific disciplines, mechanistic explanations are abundant. Because our answer to the second question is negative, our last question is ‘What kind of explanation do quantum mechanical models of atom provide?’ By addressing these questions, we shed light on the nature of an important type of chemical explanation. (shrink)

This paper aims to highlight how the philosophy of chemistry could be of help for rethinking Nature today. To do so, we will point out: the co-definition of chemical relations and chemical relata within chemical activities; the constitutive role of the modes of intervention in the definition, always open and provisional, of “active” chemical bodies; and the mutual dependence of the levels of organization in chemistry. We will insist on the way chemists tailor networks of interdependencies within which chemical bodies (...) and properties are context-sensitive and mutually determined by means of particular chemical operations or transformations. To conclude, we will show how the specific action of bodies upon the Earth at different scales of space and time, and how the relational definition of a chemical body, pave the way for a new understanding of Nature. (shrink)

This paper comments on a recent article “Revolutionary poetry and liquid crystal chemistry: Herman Gorter, Ada Prins and the interface between literature and science” by Hub Zwart, in which the author explores the influence of the liquid crystal research of Ada Prins on the epic poem Pan written by her long-time lover Herman Gorter. The present paper reviews the basic science of liquid crystals and explains the connections between the work of Prins and its influence on the poem. Other examples (...) of the use of “liquid crystal” as a literary device are identified from renaissance poetry, and the uses of the metaphor in these poems are analysed from a scientific perspective. From these examples it is suggested that creative concepts from poetry may contain elements of substance that appear in hitherto unrecognised scientific realities. (shrink)

Group 3 as Sc–Y–La, rather than Sc–Y–Lu, dominates the literature. The history of this situation, including involvement by the IUPAC, is summarised. I step back from the minutiae of physical, chemical, and electronic properties and explore considerations of regularity and symmetry, natural kinds, and quantum mechanics, finding these to be inconclusive. Continuing the theme, a series of ten interlocking arguments, in the context of a chemistry-based periodic table, are presented in support of lanthanum in Group 3. In so doing, I (...) seek to demonstrate a new way of thinking about this matter. The last of my ten arguments is recast as a twenty-word categorical philosophical statement. (shrink)

There are inherent difficulties in a subject like chemistry particularly the notion of a chemical reaction. In this paper the difficulties are discussed from a teaching and learning perspective and from a history of chemistry perspective. Three teaching/learning studies of the incompleteness of the iron thiocyanate reaction in chemical equilibrium are reviewed and it is shown that a recent historical study of the iron thiocyanate reaction has the potential to challenge the interpretation of the incompleteness of the reaction. This establishes (...) a controversial context where students can be introduced to epistemic thinking, that is, how to interrogate chemistry data and form a conclusion which resonates with what we know about the nature of science. A curriculum suggestion for pre-service chemistry teachers is provided. (shrink)

Despite the periodic table having been discovered by chemists half a century before the discovery of electronic structure, modern designs are invariably based on physicists’ definition of periods. This table is a chemists’ table, reverting to the phenomenal periods that led to the table’s discovery. In doing so, the position of hydrogen is clarified.

The statements and arguments based on experimental evidence used to support the claim that the 3d sub-level is below the 4s sub-level in scandium are examined. The flaw in all the arguments is that they assume the order in which the 3d and 4s sub-levels arrange remains the same in both the neutral atom and in its ions. Analysis of the ground and excited states of atomic spectra shows that as the number of electrons relative to the nuclear charge increases, (...) the 3d level moves higher in energy relative to the 4s level. It is perfectly possible that in a neutral scandium atom the 3d sub-level is above the 4s sub-level and that when it ionizes the energy levels simultaneously rearrange during the process. (shrink)

In the original publication of the article, the author has identified four belated corrections which are listed below.

A large variety of periodic tables of the chemical elements have been proposed. It was Mendeleev who proposed a periodic table based on the extensive periodic law and predicted a number of unknown elements at that time. The periodic table currently used worldwide is of a long form pioneered by Werner in 1905. As the first topic, we describe the work of Pfeiffer, who refined Werner’s work and rearranged the rare-earth elements in a separate table below the main table for (...) convenience. Today’s widely used periodic table essentially inherits Pfeiffer’s arrangements. Although long-form tables more precisely represent electron orbitals around a nucleus, they lose some of the features of Mendeleev’s short-form table to express similarities of chemical properties of elements when forming compounds. As the second topic, we compare various three-dimensional helical periodic tables that resolve some of the shortcomings of the long-form periodic tables in this respect. In particular, we explain how the 3D periodic table “Elementouch”, which combines the s- and p-blocks into one tube, can recover features of Mendeleev’s periodic law. Finally we introduce a topic on the recently proposed nuclear periodic table based on the proton magic numbers. Here, the nuclear shell structure leads to a new arrangement of the elements with the proton magic-number nuclei treated like noble-gas atoms. We show that the resulting alignments of the elements in both the atomic and nuclear periodic tables are common over about two thirds of the tables because of a fortuitous coincidence in their magic numbers. (shrink)

Chemistry and dynamics are closely related in G.W. Leibniz's thinking, from the corpuscularism of his youth to the theory of conspiracy movements that he proposes in his later years. Despite the importance of chemistry and chemical thought in Leibniz's philosophy, interpreters have not paid enough attention to this subject, especially in the recent decades. This work aims to contribute to filling this gap in Leibnizian studies. In this first part of the work I will expose the theory of matter that (...) the young Leibniz conceives under the influence of chemical corpuscularism. Leibniz uses R. Boyle's interpretation of the Aristotelian idea of form in order to give an explanation of the unity and cohesion of bodies. As opposed to the Cartesians, Leibniz puts forth the idea of a dependence between the variables of extension, movement and figure, without losing analytical clarity and with the aim of extending the explanatory power of physics to natural phenomena difficult to approach by Cartesian mechanics. (shrink)

Algorithmic chemistries are often based on a fixed formalism which limits the fragment of chemistry expressible in the domain of the models. This results in limited applicability of the models in contemporary mathematical chemistry and is due to the poor fit between the logic used for model construction and the system being modeled. In this paper, I propose a system-oriented methodology which selects a formalism through a mapping of chemical transformation rules to proof-theoretic structural rules. Using a formal specification framework (...) from the field of artificial chemistry, expressive adequacy is ensured by the choice of logic being based on the system properties to be modeled. To illustrate the methodology, a case study is provided that shows how the proposed approach selects linear logic for modeling resource sensitivity and the proof-theoretic interpretation facilitates translation to a programming language. Since the method results in a plurality of models, I conclude with a discussion on how the proposal contributes to multi-model paradigms in computational pharmacology. (shrink)

In the accompanying article in this issue Neuss challenges the explanation that was first suggested by Schwarz for how to teach the relative occupation and ionization of atomic orbitals in the atoms of metals in the first transition series. The present article is a response to Neuss’ critique which includes a detailed examination of his claim that there is no conclusive evidence for the view that the scandium and other first transition metal atoms lose 4s electrons in preference to those (...) located in 3d orbitals. (shrink)