Philosophy of Chemistry

The concept of green chemistry dominated the imagination of environmentally-minded chemists over the last thirty years. The conceptual frameworks laid by the American Environmental Protection Agency scholars in the 1990s constitute today the core of a line of thinking aimed at transforming chemistry into a sustainable science. And yet, in the shadow of green chemistry, a broader, even if less popular, concept of sustainable chemistry started taking shape. Initially, it was either loosely associated with green chemistry or left undefined as (...) a distinct but generaly different approach. In such a vague form, it was endorsed by the organizations such as OECD and the IUPAC in the late 1990s. It was not until the 2010s however, when it solidified as a separate more embracing and more overarching tradition that could compete with green chemistry by offering insights that the latter lacked. Sustainable chemistry seeks to transcend the narrow focus on chemical synthesis and embrace a much more holistic view of chemical activities including social responsibility and sustainable business models. Due to an interesting historical coincidence, it was in Germany where sustainable chemistry took roots and became institutionalized for the first time. It was thanks to German exceptionalism and the unwillingness of German scholars to embrace the “green” terminology originating from the US, the concept of sustainable chemistry could safely mature and develop in the German-speaking world, before reaching a high degree of formalization with dedicated journals, founding articles, and programmatic principles aspiring to transform the entire chemical enterprise in the years to come. (shrink)

Dr. K. Wray (2022) questioned my suggestion that T. W. Richards should be included as one of the scientists who contributed to the discovery of isotopes. This article provides additional support for inclusion of Richards as a contributor to the discovery.

It is a fundamental cornerstone of thermodynamics that entropy (SU,V\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$S_{U,V}$$\end{document}) increases in spontaneous processes in isolated systems (often called closed or thermally closed systems when the transfer of energy as work is considered to be negligible) and achieves a maximum when the system reaches equilibrium. But with a different sign convention entropy could just as well be said to decrease to a minimum in spontaneous constant U, V processes. It would then (...) change in the same direction as the thermodynamic potentials in spontaneous processes. This article discusses but does not advocate such a change. (shrink)

The aim of the series of the three articles entitled “Name game…” is to present the historical information about nomenclature history of every known chemical element. The process of naming each chemical element is analyzed, with particular emphasis on the first publication with a given name. It turned out that in many cases this information is not obvious and unambiguous, and the published data are even contradictory. In a few cases, the names of the elements were changed even several times. (...) Moreover, even when the author of a given element name is known, it is sometimes not entirely clear in which publication he/she first used it. Therefore, the series of three articles are an attempt to sort out the issue of first publishing of the names of all 118 chemical elements known so far, based on original source texts, available thanks to the digitization of a number of collections of scientific literature. The articles are divided according to the time of discoveries: (1) research till the end of the 18th century, (2) discoveries in the 19th century, (3) discoveries and syntheses of elements in the 20th and 21st centuries. This particular article presents the history of naming of the first 37 elements: known from antiquity, discovered in nature and named in 17th and 18th century. (shrink)

According to process ontology in the philosophy of biology, the living world is better understood as processes rather than as substantial individuals. Within this perspective, an organism does not consist of a hierarchy of structures like a machine, but rather a dynamic hierarchy of processes, dynamically maintained and stabilized at different time scales. With this respect, two processual approaches on enzymes by Stein (Hyle Int J Philos Chem 10(4):5–22, 2004, Process Stud 34:62–80, 2005, Found Chem 8:3–29, 2006) and by Guttinger (...) (Everything Flows: Towards a Processual Philosophy of Biology, Oxford University Press, Oxford, 2018) allows to think of macromolecules as relational and processual entities. In this work, I propose to extend their arguments to another case study within the biochemical domain, which is the case of ligand receptors and receptor-mediated biosignaling. The aim of this work is to analyze the case of G Protein-Coupled Receptors and biosignaling under the consideration of a processual ontology. I will defend that the processual ontology framework is adequate for the biochemical domain and that it allows accounting for the current biochemical knowledge related to the case study. (shrink)

Abstract‘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. (Ochiai, Found Chem 22:77–86, 2020a, Found Chem 22:457–465, 2020b, A philosophical essay on molecular structure, Cambridge Scholars Publishing, Newcastle upon Tyne, pp 147–174, 2021) 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)

Formal charge and oxidation state are two means of estimating the charge of an atom in a molecule. Though these concepts have very different origins—formal charge is derived from the ball-and-hook model of bonding and oxidation state is based on the ionic approximation of molecules—they are used to predict reactivity and other molecular properties through their properties as charges. In this submission, it is shown that formal charge and oxidation state are two extreme descriptions of bonding: formal charge represents zero (...) charge transfer between atoms while oxidation state represents complete charge transfer in each bond. These ‘localised electron approximations’ form an incomplete picture of atomic charge. Electronegativity measures the extent of polarity in real bonds; this concept can be introduced to polarise bonds relative to the ‘equal sharing model’. It is shown that the various electronegativity models are fundamentally related. We chose two models to demonstrate numerically that polar bonds yield charges intermediate between the localised electron approximations: Pauling and Mulliken. It is shown that probabilistic interpretation of the Pauling scale (‘scaled Pauling’ method) and use of asymmetric chemical potential (‘modified Mulliken’ method) lead to atomic charges that closely approximate experimental values using simple ‘back of the envelope’ calculations. It is seen that formal charge, oxidation state, and electronegativity-interpolated charge lie on a continuum and are mathematically related. It is therefore concluded that electronegativity introduces (quantum) delocalisation to the localised (classical) picture of electron bonding. (shrink)

Many philosophers attribute extraordinary importance to the idea of natural kinds seemingly intimating that the very possibility of certain kinds of activity are ontologically beholden to the existence of kinds. Specifically, regarding chemistry, Brian Ellis intimated that the success of any plausible metaphysical essentialism depends upon its “reliance on examples from chemistry.” Ellis’s view is representative of a tradition in analytic philosophy that has utilized chemical examples as paradigmatic natural kinds. In this regard, Kripke and Putnam emerge as the architects (...) of an entrenched research program dedicated to the chemical tradition of natural kinds in analytic philosophy. The emergence of a critical body of literature by philosophers of chemistry and others has shattered the complacent reliance upon chemical examples as exemplary kinds. On the basis of this emerging critical literature, I will critically explore the way in which chemical practice and inquiry affects the natural kind debate. So, instead of the pretense that we simply carve nature at its joints, we need to become better grounded in the practice of science, and especially with regard to the debate about natural kinds in chemical practice. Consistent with this orientation, we need to make the practice turn, that is, eradicate the fantasy of logical reconstruction and become involved with the interpretative and historical challenges of understanding the nuances of practice. The point here is quite clear, metaphysical questions regarding natural kind should be imminent to scientific practice. Indeed, any legitimate metaphysics of natural kinds should be appropriately informed and grounded in practice and not operate on the basis of a priori sovereignty. I will insert this critical discussion within the analytical context of the notion of interpretive communities and make the case that philosophers should not assume that appeals to the purity of philosophy can substitute for the complexity and practical orientation of chemical practice. (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)

Mental model construction is supposed to be a useful cognitive devise for learning. Beyond human capacity of constructing mental models, scientists construct complex explanations about phenomena, named scientific or theoretical models. In this work we revisit three vissions: the first one concern about the polisemic term “model”. Our proposal is to discriminate between “mental models” and “explicit models”, being the former those “imaginistic” ideas constructed in scientists’—o teachers—minds, and the latter those teaching devices expressed in different languages that tend to (...) communicate any “scientific model”. From this point of view, the class is considered a place where teachers’ mental models should be learned by novice students by decoding their teaching devices which are expressed in different languages. Other proposal of this work claims to distinguish the term “representation” with respect to its artistical or instrumental origin, highlighting that they are types of teaching devices and that artistical representations are always analogies. Finally, data about the construction of freshmen’s wrong mental models related to the use of the analogy between the chemical combustion and the global process of cellular respiration from glucose is presented to reinforce previous epistemological reflections. (shrink)

Based upon the demarcation between Elementalism and Atomism Chemistry from the perspective of the long-term history of chemistry, the authors re-examine the Berthollet-Proust controversy on the three types of chemical compounds, pointing out that Berthollet proposed the law of indefinite proportions by deduction, while Proust proposed the law of definite proportions by induction. The controversy is beyond the framework of affinity chemistry and entail a synthesis of meta-chemical thinking and experiments. Proust’s discovery of the law of definite proportions not only (...) function as Bacon’s “instances of lamp” to invoke Dalton and other atomism chemists to envision atomism, but also served as a bridge linking the two meta-chemistries. John Dalton, the third choice, envisioned his atomism by abduction. The case study on “the Berthollet-Proust controversy and Dalton’s resolution” mandates a reinvestigation of the crucial role of the system of experiments and the evolution of chemistry according to the demarcation between the established branches of Elementalism and Atomism Chemistry. (shrink)

Are acids natural kinds? Or are they merely relevant kinds? Although acidity has been one of the oldest and most important concepts in chemistry, surprisingly little ink has been spilled on the natural kind question. I approach the question from the perspective of microstructural essentialism. After explaining why both Brønsted acids and Lewis acids are considered functional kinds, I address the challenges of multiple realization and multiple determination. Contra Manafu and Hendry, I argue that the stereotypical properties of acids are (...) not multiply realized. Instead, given the equivalence between the proton-donating and electron-accepting mechanisms of Brønsted and Lewis, respectively, I show that acidity as a property type can be identified with a unique microstructural property, namely the presence of a LUMO or other low energy empty orbital. In doing so, I defend the view that the Lewis theory encompasses Brønsted--Lowry, and that all Brønsted acids are also Lewis acids. Contra Hacking and Chang, I thus maintain that the different concepts of acidity do not crosscut, and that the hierarchy requirement is met. Finally, by characterizing natural kinds as powerful objects and by adopting a dispositional view of functions, I illustrate how the microessentialist can make sense of the latent and relational character of most acids. In sum, I contend that acids are genuine natural kinds, even for the microstructural essentialist. (shrink)

This book represents an original journey beginning from the simple and undifferentiated atom, to differentiated atoms, to molecules, to macromolecules, and to the thresholds of life. One of the most important aims of this book is to underline the philosophical function of the concept of molecule. The description of the material world permitted by the concept of structured entity has revolutionized the entire scientific worldview. Moreover, the concept of macromolecule has projected the molecular world towards the threshold of the biological (...) world and this analysis will also form an integral part of this book. The scientific and epistemological approach towards the molecular world will also serve to link chemistry with philosophy proper. Up to the 19th century, chemistry had enjoyed its own philosophical foundation, which was anchored in the concept of atom, a concept with a rich philosophical heritage. The 20th century appropriation of this concept by physicists has deprived chemistry of its distinctive philosophical foundation, relegating it being merely an applied branch of physics. In this regard, we consider the concept of molecular structure as an exquisitely philosophical concept and as the strong point permitting a solid differentiation of chemistry from physics. The recuperation of a fertile relationship between chemistry and philosophy can and must occur around the concept of structured and complex reality. Chemistry can be projected to the cultural vanguard but only if its practitioners once again attend to the conceptual and philosophical concerns within their discipline, albeit without abandoning the technical concerns that are essential to modern science. (shrink)

Examples are given of applications by Pauling, Mulliken, Marcus and G.E.Kimball of the three Pythagorian means to formulate the scales of electronegativity of the elements, to the calculations of rate constants of electron transfer cross-reactions, to the calculation of the observed rate constant as function of activation and diffusion rate constants in the case of mixed reaction-diffusion rates and to the calculation of the effective diffusion coefficient in solution of a salt AB as a whole from the diffusion coefficients of (...) the ions in which it dissociates. (shrink)

Despite decades of research and thought on the meaning and identification of revolutions in science, there is no generally accepted definition for this concept. This paper presents 13 different characteristics that have been used by philosophers and historians of science to characterize revolutions in science, in general, and in chemistry, in particular. These 13 characteristics were clustered into six independent factors. Suggestions are provided as to the use of these characteristics and factors to evaluate historical events as to their possible (...) categorization as revolutions in chemistry. Challenges to the goal of creating a consensus definition of “revolutions in science” are also presented in this publication. (shrink)

Recent publications by several leading philosophers of chemistry have focused on the definition, scope, utility, and nomenclature of issues dealing with acidity and basicity. In this paper, molecular orbital theory is used to explain all acid–base reactions, concluding that the interaction of the highest occupied molecular orbital (HOMO) of one substrate, “the base,” with the lowest unoccupied molecular orbital (LUMO) of a second substrate, “the acid,” determines the reactivity of such systems. This paradigm provides an understanding of all acid–base reactions (...) as well as other reactions which, on the surface, may not seem like acid–base reactions but which have fundamental underpinnings of that kind of chemistry. Rather than being unable to determine a unified understanding of acidity and basicity as suggested in the philosophy of chemistry literature, we propose that acidity and basicity fit securely in a classification of many other reactions that, using classical chemistry knowledge, pre-quantum chemistry, would not be possible. We strongly support the use of all scientific knowledge and experience in the development of the ideas in the philosophy science. We further suggest increased interactions between philosophers of science and scientists, so that all scholars benefit from the values, knowledge, and perspectives of other disciplines. (shrink)

Consider chemical elements as a system, we create an undirected chemical network with 99 elements and 1916 edges from _Chemspider_, a website that provide search engines to collect compounds. Using this network and the network that we used in our previous work with 97 elements and 2198 edges, we found that _RootedPageRank_, a link prediction tool in complex network, can be used to predict potential binary compounds, because the changing trend of _PageRank_ probability of each element in these networks all (...) follow the periodic law, despite of the difference of scale of these networks. The accuracy test indicates that at least 7 among top 10 predicted compoundss in one network can be verified using the compoundss in the other network or in other chemical database, proving that this method can be used to provide guidance in finding potential binary compounds, suggesting that we can study chemical properties from the view of complex network. (shrink)

The second article of the “Naming game…” series provides detailed information on the discovery and naming of elements in the nineteenth century. Outlines of discoveries of 46 elements were presented, with particular emphasis on publications in which the name appeared for the first time. In the article the short historical information about every element naming is presented. The process of naming each chemical element was analyzed, with particular emphasis on the first publication with a given name.

The third article of the “Naming game…” series presents the issues of naming elements discovered and synthesized in the twentieth and twenty-first centuries. Based on the source data, the publication time of the names of the last 35 chemical elements was identified. In the case of discoveries from the end of the twentieth century and the beginning of the twenty-first century, the principle was adopted of the priority of information about the synthesis of a new chemical element in scientific journals (...) or conference reports. However, when the same information was published earlier in the news sections of scientific journals, in articles in popular science journals, and (in modern times) on the websites of interested research institutes, such an info is presented as well. It turned out that in some cases this information is very complex as the names of some elements were changed several times and published in different media in the same period. Therefore, this article is an attempt to sort out the issue of first publishing of the names of the last known 35 chemical elements. (shrink)

Robin Hendry has presented an account of two equally valid ways of understanding the nature of chemical bonding, consisting of what the terms the structural and the energetic views respectively. In response, Weisberg has issued a “challenge to the structural view”, thus implying that the energetic view is the more correct of the two conceptions. In doing so Weisberg identifies the delocalization of electrons as the one robust feature that underlies the increasingly accurate quantum mechanical calculations starting with the Heitler-London (...) method and moving on to such approaches as the valence bond and molecular orbital theories of chemical bonding. The present article provides a critical evaluation of Weisberg’s article and concludes that he fails to characterize the nature of chemical bonding in several respects. I claim that Hendry’s structural and energetic views remain as equally viable ways of understanding chemical bonding. Whereas the structural view is more appropriate for chemists, the energetic view is preferable to physicists. Neither view is more correct unless one subscribes to the naively reductionist view of considering that the more physical energetic view is the more correct one. (shrink)

The interrelation between two theories, theory of complexity and theory of systems, is analyzed by using the chemical graph-theoretical concept. The idea of complexity is systemized through three components: diachronic, synchronic, and combinatorial complexity. The relationships between entropy and complexity, as well as the problem of function are also discussed.

According to process ontology in the philosophy of biology, the living world is better understood as processes rather than as substantial individuals. Within this perspective, an organism does not consist of a hierarchy of structures like a machine, but rather a dynamic hierarchy of processes, dynamically maintained and stabilized at different time scales. With this respect, two processual approaches on enzymes by Stein (Hyle Int J Philos Chem 10(4):5–22, 2004, Process Stud 34:62–80, 2005, Found Chem 8:3–29, 2006) and by Guttinger (...) (Everything Flows: Towards a Processual Philosophy of Biology, Oxford University Press, Oxford, 2018) allows to think of macromolecules as relational and processual entities. In this work, I propose to extend their arguments to another case study within the biochemical domain, which is the case of ligand receptors and receptor-mediated biosignaling. The aim of this work is to analyze the case of G Protein-Coupled Receptors and biosignaling under the consideration of a processual ontology. I will defend that the processual ontology framework is adequate for the biochemical domain and that it allows accounting for the current biochemical knowledge related to the case study. (shrink)

In present day’s sustainable agriculture is relatively a new area which required more attention by scientist/researchers and this one treated as basic need of human survival. In past decades, sustainable agriculture meets environmental and economic goals simultaneously, that’s why this field has received widespread interest. Green Chemistry is described as the ‘‘design of chemical products and processes to eliminate or reduce the use and generation of hazardous substances. Green chemistry mainly based on 12 principles and plays a very important role (...) in environmental protection. For human development sustainable agriculture and green chemistry both are essential. This article discussed 12 proposed principles of sustainable agriculture inspired by existing 12 principles of Green Chemistry. (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)

Summary In this work we elaborate on the idea of a formal theory for a limited but important part of structural chemistry, that described by Lewis’ methods and VSEPR (Valence Shell Electron Pair Repulsion). For this purpose, recursive functions and propositional functions are defined, that apply to formal expressions of the structure, based on a finite set of symbols. This approach allows for the expression of numerous questions of chemical interest. The formalization of basic structural chemistry based on Lewis/VSEPR method (...) is potentially useful for the automation of the related procedures, but possibly also of some use as complementary material in teaching and as a heuristic tool in structural chemistry. (shrink)

From the perspective of successive events, chemical reactions are expressed or thought about, in terms of the cause-effect category. In this work, I will firstly discuss some aspects of causation and interaction in chemistry, argue for the interaction, and propose an alternative or complementary representation scheme called “interaction diagram”, that allows representing chemical reactions through a geometric diagram. The understanding of this diagram facilitates the analysis of reactions in terms of the interaction, or reciprocal action, among the participating entities. Secondly, (...) I will describe the model and provide examples and finally, I will discuss the scope and limitations of the current development status of the model. (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)

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)

An examination of some of the writings in the medical and mineralogical texts of Persia in the Middle Ages, written in the Arabic language during the caliphate period, revealed an inconsistency concerning the modern chemical identity of the substance called zinjafr, which was recognized as a medication for wounds, burns, mange, and cavities. Although some of the literature identified it as the important ore cinnabar sulfide), some questioned that identification or even ambiguously described it as a substance produced from lead. (...) A modern chemical study was conducted and identified the latter substance as minium. The reason for the medieval authors not distinguishing between those two compounds is discussed and the fact that the dictionaries of modern written Arabic commonly have the words zinjafr and cinnabar listed as equivalents is also explored. Further, the ability of Arabic alchemy to distinguish between cinnabar and minium is assessed in light of modern chemistry.Graphical abstractA 1973 Soviet postage stamp celebrating the 1000th anniversary of al-Biruni’s birth. (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)

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)

It is a notion commonly acknowledged that in his work Timaeus the Athenian philosopher Plato (_c_. 429–347 BC) 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 (fire, air, water, and earth) as well as the interpretation they received in the literature. I find that scientists and scholars generally emphasized (and often misunderstood) 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)

Immanuel Kant’s admiration of the “starry sky” above him and the “moral law” in it has become a philosophical topos today. While the “moral law” is the subject of practical philosophy, Kant refers to an object of astronomy for the main task of theoretical philosophy - namely, to answer the question “What can I know? “. Volume III tackles this question - generalizing to the “hard” sciences of physics, chemistry, and cosmology. It focuses on specific questions that have always been (...) considered “philosophical” in the broadest sense by the interested public and even among physicists themselves: “What is simultaneity at different places?”, “Which interpretation of quantum mechanics is the correct one and what follows from it for our view of the world?” – and, last but not least, “Did the universe exist from eternity or does it have a beginning (and an end)?”. (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)

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)

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)