The ArgumentMost historians of science share the conviction that the incorporation of the corpuscular theory into seventeenth-century chemistry was the beginning of modern chemistry. My thesis in this paper is that modern chemisty started with the concept of the chemicl compound, which emerged at the end of the seventeenth and the beginning of the eighteenth century, without any signifivant influence of the corpuscular theory. Rather the historical reconstruction of the emergence of this concept shows that it resulted from the (...) reflection on the chemical operations in the sixteenth-century metallurgy and seventeenth-century pharmacy. I argue that the reversibility of these operations and their understanding as crafts (metallurgy) or chemical arts (pharmacy) were decisive factors for the emergence of the first ideas about chemical compounds in the seventeenth-century pharmaceutical works written by pharmaceutically trained authors, influenced by the Paracelsian image of nature. There is a direct line of descent from these authors to E.F.Geoffroy (1675–1742), who integrated the first scattered ideas of chemical compound into a general concept comprising chemical artefacts as well as natural bodies. (shrink)

Ursula Klein has argued that Geoffroy’s table of chemical affinities, published in 1718, marked the emergence of the concepts of chemical compound and chemical combination central to chemistry. In this paper her position is summarised and then modified to render it immune to criticism that has been levelled against it. The essentials of Geoffroy’s chemistry are clarified and adapted to Klein’s picture by way of a detailed comparison of it with Boyle’s corpuscular chemistry that proceeded Geoffroy’s (...) by over half a century. The idea that Geoffroy’s notion of chemical combination marked a significant turning point in the emergence of modern chemistry is defended against the charge that it is Whiggish. (shrink)

In this article I assess the problems and prospects of a microstructural approach to chemical substances. Saul Kripke and Hilary Putnam famously claimed that to be gold is to have atomic number 79 and to be water is to be H2O. I relate the first claim to the concept of element in the history of chemistry, arguing that the reference of element names is determined by atomic number. Compounds are more difficult: water is so complex and heterogeneous at the (...) molecular level that `water is H2O' seems false under some interpretations. I sketch a response to this problem. (shrink)

In this article I assess the problems and prospects of a microstructural approach to chemical substances. Saul Kripke and Hilary Putnam famously claimed that to be gold is to have atomic number 79 and to be water is to be H2O. I relate the first claim to the concept of element in the history of chemistry, arguing that the reference of element names is determined by atomic number. Compounds are more difficult: water is so complex and heterogeneous at the (...) molecular level that `water is H2O’ seems false under some interpretations. I sketch a response to this problem. (shrink)

SummaryThis essay explains why and how nineteenth-century chemists sought to stabilize the melting and boiling points of organic substances as reliable characteristics of identity and purity and how, by the end of the century, they established these values as ‘Constants of Nature’. Melting and boiling points as characteristic values emerge from this study as products of laboratory standardization, developed by chemists in their struggle to classify, understand and control organic nature. A major argument here concerns the role played by the (...) introduction of organic synthesis in driving these changes. Synthetic organic chemistry vastly increased the number of known organic substances, precipitating the chemical identity crisis of my title. Successful natural product synthesis, moreover, depended on chemists’ ability to demonstrate the absolute identity of synthetic product and natural target – something late nineteenth-century chemists eventually achieved by making reliable, replicable melting and boiling point measurements. In the period before the establishment of national standards laboratories, chemists and scientific glassblowers worked together to standardize melting and boiling points as physical constants, such collaborations highlighting the essential importance of chemical glassware and glassblowing skill in the development of nineteenth-century organic chemistry. (shrink)

How do we refer to chemical substances, and in particular to chemical elements? This question relates to many philosophical questions, including whether or not theories are incommensurable, the extent to which past theories are later discarded, and issues about scientific realism. This chapter considers the first explicit reference to types of colorless air in late-eighteenth-century chemical practice. Reference to a gas by one chemist was generally intended to give others epistemological, methodological, and practical access to the gas. (...) This chapter proposes a causal-descriptive theory of reference for chemical substances. Implications for debates about incommensurability and realism are also briefly noted. (shrink)

Traditionally the study of chemical elements has been limited to well-known concepts like the periodic properties and chemical families. However, current information shows a new and rich language that allows us to observe relations in the elements that are not limited to their positions in the table. These relations are evident when reactions are represented through networks, as in the case of similar reactivity of organic compounds sharing functional groups. For the past two decades, it has been argued (...) that network reactions may be considered the core of chemistry. This network, which constitutes the basic set of chemical knowledge, provides the basis for classification and delivers routes to obtain new and known substances. In order to provide an example, we constructed and analyzed a network of chemical elements from the formation of stoichiometric binary compounds, providing to the chemistry, a formal structure of extracting the chemical knowledge. Thus, we explored all possible presence of relationships among elements. Concepts like degree centrality and centralization, the relationships among metals, semimetal and nonmetal classes, blocks, and chemical families were analyzed. We observed that the network structure had a small core set of elements of high reactivity and also a peripheral set of elements of low reactivity. The classes, blocks and families show the following increasing order of reactivity: nonmetals > semimetals > metals; p > s > d > f; and families: boron, carbon, pnictogens, chalcogens, halogens, lanthanoids > other families. This example shows, from the network perspective, that the elements and their classifications exhibit properties such as the reactivity, order, and similarity. (shrink)

SummaryThe convening of the first three Solvay Chemistry Conferences in Brussels from 1922–1928 marked an important turning point for the discipline of chemistry. Whereas much of nineteenth-century chemical endeavour had focused on compositional and functional analysis of chemical compounds, many leaders in chemistry were turning to questions of molecular dynamics by the early twentieth century. Two competing schools of chemical dynamics, which were represented at the Solvay Conferences, were a predominantly English group (Lowry, Lapworth, Robinson, Ingold) who (...) worked out electron and ionic interpretations of organic reaction mechanisms, and a French group (Perrin, Job) who developed a generalized radiation hypothesis of reaction activation. While differences in conceptual and stylistic approach separated the two schools, they agreed on the need to apply contemporary physical theory to old chemical problems, and to develop a theoretical chemistry complementary to theoretical physics. (shrink)

We are immersed within an odorous sea of chemical currents that we parse into individual odors with complex structures. Odors have been posited as determined by the structural relation between the molecules that compose the chemical compounds and their interactions with the receptor site. But, naturally occurring smells are parsed from gaseous odor plumes. To give a comprehensive account of the nature of odors the chemosciences must account for these large distributed entities as well. We offer a focused (...) review of what is known about the perception of odor plumes for olfactory navigation and tracking, which we then connect to what is known about the role odorants play as properties of the plume in determining odor identity with respect to odor quality. We end by motivating our central claim that more research needs to be conducted on the role that odorants play within the odor plume in determining odor identity. (shrink)

From a modern point of view, compounds are contrasted with elements of which they are composed, and the two categories combine to give the category of substances. Mixtures, on the other hand, might be understood to contrast with pure substances (substances in isolation), so that mixtures are quantities of matter containing several substances (be they compounds or uncombined elements) whereas pure substances are understood to be quantities of matter exhausting the material contents of a region of space which contain only (...) one substance, and might be either a compound or an element. But heterogeneous quantities of matter (comprising several phases) might also be understood to be mixtures. Thus, it is common to speak of a mixture of ice, liquid water and water vapour in equilibrium at the triple point of water, although there is only a single substance present. The general concept of mixture as treated by Gibbs’ phase rule is a quantity of matter comprising either several substances or several phases, “or” being used in the inclusive sense. Gibbs’ phase rule is a relatively recent development in the history of the concept of chemical substance, dating from the latter half of the nineteenth century. The concepts and distinctions it presupposes have not always been apparent. I trace some of the important conceptual developments underlying the important distinctions at issue here from Aristotle, who didn’t distinguish either substance and phase, or what are now called compounds and solutions. (shrink)

The ArgumentThe overall portrayal of early modern experimentation as a new method of securing assent within a philosophical discourse sketched in many of the recent studies on the historical origin of experimentation is questioned by the analysis of the experimental practice of chemistry at the Paris Academy. Chemical experimentation at the Paris Academy in the late seventeenth and early eighteenth century originated in a different tradition than the philosophical. It continued and developed the material culture of the chemical (...) work shops of the sixteenth and seventeenth centuries, and explored epistemic objects which had rather loose connections to philosophy. On the other hand, I argue against the classical dichotomy between the work of the mind that of the hand, and for an epistemology of experimentation that acknowledges that experimental manipulation goes hand in hand with reflexion. In particuler, I argue against the view that chemists at the Paris Academy were “pragmatists” who merely gathered experimental facts and classified substances and operations without perplexing themselves over general conceptions. I claim that the chemists at the Paris Academy constructed a general conception framework which shaped the significance of their experiments. This conception that I call conception of the chemical combination, compound and reaction was rather quickly reified into an experimental fact. Despite its generality it was a genuine chemical conception rather independent of philosophy. (shrink)

The main scientific problems of chemical bonding were solved half a century ago, but adequate philosophical understanding of chemical combination is yet to be achieved. Chemists routinely use important terms ("element," "atom," "molecule," "substance") with more than one meaning. This can lead to misunderstandings. Eliminativists claim that what seems to be a baseball breaking a window is merely the action of "atoms, acting in concert." They argue that statues, baseballs, and similar macroscopic things "do not exist." When macroscopic (...) objects like baseballs move, exceedingly large numbers (1025) of microscopic components coordinate their activities. Understanding how this happens requires attention to the interactions that link parts into larger units. Eliminativists say that everything that truly exists has causal relationships in addition to those of its components—"nonredundant causality." This paper holds that if a number of entities interact in such a way that the effect of that collection on test objects is different than it would have been in the absence of the interaction, then identification of that collection as a single composite agent is warranted, for purposes to which that difference is relevant. Ordinary "chemical substances" (both elementary materials such as dihydrogen and compounds such as water) fulfill this version of the requirement of nonredundant causality. Other sorts of chemical coherences, including chemical dissipative structures (e.g., flames), also fulfill that criterion. All these types of coherences qualify as "substances" (as that term is used in philosophy) even though they are not all "chemical substances.". (shrink)

This paper is a study of a distinctively chemical notion of possibility. This is the notion of possibility that occurs in chemical discourses when chemists speak of the possibility or impossibility of achieving a given result through chemical means. This notion pertains to the possibility of processes, not of compounds, so it differs from the kind of chemical possibility mentioned in Wittgenstein's Philosophical Investigations or the kinds discussed in the literature on Putnam's Twin Earth argument. I (...) argue that this process-oriented notion of possibility cannot be reduced in a simple way to physical possibility, and that standard possible worlds semantics does not allow a natural analysis of this notion. I suggest an extension of possible worlds semantics that may overcome this limitation. I finish by pointing out some open questions about chemical possibility. (shrink)

In this article I examine several related views expressed by Robin Hendry concerning molecular structure, emergence and chemical bonding. There is a long-standing problem in the philosophy of chemistry arising from the fact that molecular structure cannot be strictly derived from quantum mechanics. Two or more compounds which share a molecular formula, but which differ with respect to their structures, have identical Hamiltonian operators within the quantum mechanical formalism. As a consequence, the properties of all such isomers yield precisely (...) the same calculated quantities such as their energies, dipole moments etc. The only means through which the difference between the isomers can be recovered is to build their structures into the quantum mechanical calculations, something that is carried out by the application of the Born-Oppenheimer approximation. Consequently, it has been argued by many authors that molecular structure is written in ‘by hand’ rather than derived. Robin Hendry is one such author, but he goes a great deal further by proposing that this situation implies the existence of emergence and downward causation. In the current article I argue that there are alternative explanations which render emergence and downward causation redundant. Such an alternative lies in the notion of quantum decoherence and the appeal to work in the foundations of physics, which posits that the various isomers exist as a superposition until their wavefunctions are collapsed either by observation or by interacting with their environment. Hendry also alludes to a debate among chemists as to whether chemical bonds are real or not, in the sense of directional connections between two or more nuclei in any given molecule. I reject this view and propose that the structural and energetic views of chemical bonding, that have been discussed by some philosophers of chemistry including Hendry, do not refer to any essential ontological differences. I agree that chemists view bonding in a more realistic fashion and may consider bonds to be in some senses real, while physicists may consider bonding in more abstract energetic terms. However, I do not believe that such differences in scientific practice and attitudes should be considered to offer a window as to the ontological status of bonding or whether bonding is real. Finally, I discuss the kinetic energy school of chemical bonding which would seem to challenge any notion of bonds as directional entities, since bonding is no longer regarded as being primarily due to the build-up of electron density between nuclei. (shrink)

One of the central debates among British chemists during the 1830s concerned the use of symbols to represent elements and compounds. Chemists such as Edward Turner, who desired to use symbolic notation mainly for practical reasons, eventually succeeded in fending off metaphysical objections to their approach. These objections were voiced both by the philosopher William Whewell, who wished to subordinate the chemists' practical aims to the rigid standard of algebra, and by John Dalton, whose hidebound opposition to abbreviated notation symbolized (...) the suspicion with which older British chemists perceived continental innovations. It is argued that the success of chemists like Turner in this debate reflects their larger success in the 1830s in achieving disciplinary autonomy and in beginning to align themselves more closely with prevailing chemical practice across the Channel. (shrink)

Similarities in properties among pairs of metallic elements and their compounds in the lower-right quadrant of the Periodic Table have been named the ‘Knight’s Move’ relationship. Here, we have undertaken a systematic study of the only two ‘double-pairs’ of ‘Knight’s Move’ elements within this region: copper-indium/indium-bismuth and zinc-tin/tin-polonium, focussing on: metal melting points; formulas and properties of compounds; and melting points of halides and chalcogenides. On the basis of these comparisons, we conclude that the systematic evidence for ‘Knight’s Move’ relationships (...) derives from similarities in formulas and properties of matching pairs of compounds in the same oxidation state. Physical properties, such as melting points, do not provide consistent patterns and trends and hence should not be considered as a common characteristic of this relationship. (shrink)

The exploration of chemical periodicity over the past 250 years led to the development of the Periodic System of Elements and demonstrates the value of vague ideas that ignored early scientific anomalies and instead allowed for extended periods of normal science where new methodologies and concepts are developed. The basic chemical element provides this exploration with direction and explanation and has shown to be a central and historically adaptable concept for a theory of matter far from the reductionist (...) frontier. This is explored in the histories of Prout’s hypothesis, Döbereiner Triads, element inversions necessary when ordering chemical elements by atomic weights, and van den Broeck’s ad-hoc proposal to switch to nuclear charges instead. The development of more accurate methods to determine atomic weights, Rayleigh and Ramsey’s gas separation and analytical techniques, Moseley’s X-ray spectroscopy to identify chemical elements, and more recent accelerator-based cold fusion methods to create new elements at the end of the Periodic Table point to the importance of methodological development complementing conceptual advances. I propose to frame the crossover from physics to chemistry not as a loss of accuracy and precision but as an increased application of vague concepts such as similarity which permit classification. This approach provides epistemic flexibility to adapt to scientific anomalies and the continued growth of chemical compound space and rejects the Procrustean philosophy of reductionist physics. Furthermore, it establishes chemistry with its explanatory and operational autonomy epitomized by the periodic system of elements as a gateway to other experimental sciences. (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)

In this article I examine several related views expressed by Robin Hendry concerning molecular structure, emergence and chemical bonding. There is a long-standing problem in the philosophy of chemistry arising from the fact that molecular structure cannot be strictly derived from quantum mechanics. Two or more compounds which share a molecular formula, but which differ with respect to their structures, have identical Hamiltonian operators within the quantum mechanical formalism. As a consequence, the properties of all such isomers yield precisely (...) the same calculated quantities such as their energies, dipole moments etc. The only means through which the difference between the isomers can be recovered is to build their structures into the quantum mechanical calculations, something that is carried out by the application of the Born-Oppenheimer approximation. Consequently, it has been argued by many authors that molecular structure is written in ‘by hand’ rather than derived. Robin Hendry is one such author, but he goes a great deal further by proposing that this situation implies the existence of emergence and downward causation. In the current article I argue that there are alternative explanations which render emergence and downward causation redundant. Such an alternative lies in the notion of quantum decoherence and the appeal to work in the foundations of physics, which posits that the various isomers exist as a superposition until their wavefunctions are collapsed either by observation or by interacting with their environment.Hendry also alludes to a debate among chemists as to whether chemical bonds are real or not, in the sense of directional connections between two or more nuclei in any given molecule. I reject this view and propose that the structural and energetic views of chemical bonding, that have been discussed by some philosophers of chemistry including Hendry, do not refer to any essential ontological differences. I agree that chemists view bonding in a more realistic fashion and may consider bonds to be in some senses real, while physicists may consider bonding in more abstract energetic terms. However, I do not believe that such differences in scientific practice and attitudes should be considered to offer a window as to the ontological status of bonding or whether bonding is real. Finally, I discuss the kinetic energy school of chemical bonding which would seem to challenge any notion of bonds as directional entities, since bonding is no longer regarded as being primarily due to the build-up of electron density between nuclei. (shrink)

Though complex networks have been widely applied in the research of chemistry, there is hardly any introduction about the establishment of networks using chemical bonds. In this paper, we consider chemical elements as a system linked by chemical bonds and create the undirected chemical bond network by abstracting nodes from elements and undirected edges from bonds. Connectivity, heterogeneity, small world and disassortativity of this network show the macro structural rationality of this system. The degree and k-order (...) neighbors of an element, which represent the micro topology of this network, can be used to measure its chemical reactivity and detect how many kinds of compounds it can form. The similarity between two elements is measured by the Jaccard index and the VOS mapping technique, results of which are similar to well-known similarities between elements shown by the periodic table. The establishment and topological analysis of this network provide another way to understand and study elements and bonds, and more chemical properties of elements and bonds can be studied by complex networks. (shrink)

Exposure of man to chemical agents can occur intentionally, as in the treatment of disease, or inadvertently because the environment contains a wide range of synthetic or naturally occurring chemicals. The alkylating agents are a diverse group of compounds (Fig. 1) and comprise a good example of such xenobiotics, since much is known about their occurrence, and their biological effects include carcinogenicity, mutagenicity, toxicity and teratogenicity.Exposure to potentially carcinogenic alkylating agents such as nitrosamines may occur occupationally, from cigarette smoke, (...) from certain foodstuffs and even endogenously through the ingestion of the appropriate precursor chemicals.1 At the other extreme, the cytotoxic effects of agents such as the chloroethylating nitrosamides or mustards have been exploited in the design of certain antitumour drugs.2 The effectiveness of antitumour agents and the other, mostly adverse, biological effects of alkylating agents have been ascribed to their ability to damage cellular macromolecules, in particular DNA. This review concentrates on investigations carried out over the past two years on the role of DNA damage in carcinogenesis, but we shall see how recent advances in this area of research have also led to a better understanding of the mechanisms of the cytotoxic effects of alkylating antitumour agents. (shrink)

In the course of developing his theory of what would now be called chemical substance, Aristotle introduces what appear to be two distinct definitions of element alongside his notion of mixt (homogeneous mixture). The present paper is concerned with the integration of these ideas in a uniform theory, which calls for some speculation about the import of elemental proportions in compounds.

Contingentism, generally contrasted with law necessitarianism, is the view that the laws of nature are contingent. It is often coupled with the claim that their contingency is knowable a priori. This paper considers Bird's (2001, 2002, 2005, 2007) arguments for the thesis that, necessarily, salt dissolves in water; and it defends his view against Beebee's (2001) and Psillos's (2002) contingentist objections. A new contingentist objection is offered and several reasons for scepticism about its success are raised. It is concluded that (...) certain higher-level laws describing the behaviours of molecular compounds may be necessary due to their dependence on underlying physical laws, and that the modal status of laws of nature cannot be determined a priori, as the structural features of the substances and properties they govern must first be investigated. (shrink)

This is a translation of part of Fr. Hoenen’s Cosmologia in which the author sets out, so the translator tells us in the preface, to discover the philosophical explanation of non-living or inorganic compounds. One wonders why he decided to equate non-living with inorganic and to omit a number of organic compounds which are also non-living. The book makes heavy reading for the English is prolix, awkward and jejune. One gets the impression too that the translator is not exactly at (...) home in the field of chemistry. When quoting chemical laws it would have been better to employ some standard formula which would have avoided such clumsy statements as the following: ‘Given gases at a constant temperature and pressure, the volumes of the component gases taking part in a reaction are in simple proportion to one another and to the volume of the chemical compound’. Again on p. 36 we find: ‘The Molecular theory, in so far as it is now confirmed, may be stated thus: Gaseous bodies consist of molecules as of parts actually discrete’. (shrink)

Human UDP‐glucuronosyltransferases (UDPGTs) are a family of enzymes which detoxify many hundreds of compounds by their conjugation to glucuronic acid, rendering them both harmless and more water soluble, hence, excretable. The level of expression of each UDPGT isoform in the body is the result of interplay between temporal, tissue‐specific and environmental regulators. This complexity contributes to the difficulty in predicting the metabolic fate of compounds.Genetic defects and polymorphisms affecting individual isoform activities have deleterious and potentially lethal effects, as exemplified by (...) the severe hyperbilirubinaemia observed in Crigler‐Najjar Syndrome. Such severe genetic defects in bilirubin glucuronidation are obvious candidates for antenatal screening and gene therapy. (shrink)

A 4-dimensional periodic table of chemical elements is presented. The 120 elements in the n = 8 system are located on vertices of a 4D-cubic lattice and specified by Cartesian coordinates based on the four quantum numbers. Each quantum number is represented by a vector along a different spatial direction in 4D Euclidean space. The 4D PT has a fixed topology governed by Euler–Poincare-type equation and the chemical elements have a fixed connectivity with neighboring elements within the 4D (...) PT. Various geometric transformations by rotations and elongations of vectors enable morphing of one PT to another in a continuum while preserving the 4D topology. The 4D structure exhibits principles of complementarity and zero-cyclic sum in chemical elements. Complementarity enables the extension to n = 9 elements and beyond. The 4D PT of elements extends to isotopes and also to molecules and compounds with the same underlying principles. (shrink)

When “general physiology” emerged as a basic field of research within biology in the early nineteenth century, Henri Ducrotay de Blainville (1777–1850) on the one hand and Johannes Peter Müller (1801–1858) on the other appealed to chemical analysis to account for the properties and operations of organisms that were observed to differ from what was found in inorganic compounds. Their aim was to establish laws of vital organization that would be based on organic chemical processes, but would also (...) be of use to explain morphological and functional differences among life forms. The intent of this paper is to specify for each of these leading physiologists the different presuppositions that provided theoretical frameworks for their interpretation of what they conceived of as laws of organization underpinning the dynamics of vital phenomena. Blainville presumed that the properties of organic compounds depended on the chemical properties of their constitutive molecules, but combined according to patterns of functional development, and that the latter could only be inferred from an empirical survey of modes of organization across the spectrum of life forms. For Müller, while all vital processes involved chemical reactions, in the formative and functional operations of organisms, these reactions would result from the action of life forces that were responsible for the production of organic combinations and thus for vital and animal functions. As both physiologists set significant methodological patterns for their many disciples and followers, their respective quasi-reductionist and anti-reductionist positions need to be accounted for. (shrink)

The Aristotelian notion of a proper mixture is that of a homogeneous body potentially separable into a definite proportion of elements. Its relation to more modern chemical ideas is not without interest despite the success of modern atomic theory. But there is a fundamental conflict entailed by Aristotle’s two approaches to the characterisation of elements, one in terms of the properties they exhibit in isolation and another in terms of their role as constituents of compounds. Although one source of (...) problems for Aristotle has been put aside in modern chemistry, it seems that the underlying tension remains an issue. (shrink)

Periodic tables (PTs) are the ‘ultimate paper tools’ of general and inorganic chemistry. There are three fields of open questions concerning the relation between PTs and physics: (i) the relation between the chemical facts and the concept of a periodic system (PS) of chemical elements (CEs) as represented by PTs; (ii) the internal structure of the PS; (iii)␣The relation between the PS and atomistic quantum chemistry. The main open questions refer to (i). The fuzziness of the concepts of (...) chemical properties and of chemical similarities of the CE and their compounds guarantees the autonomy of chemistry. We distinguish between CEs, Elemental Stuffs and Elemental Atoms. We comment on the basic properties of the basic elements. Concerning (ii), two sharp physical numbers (nuclear charge and number of valence electrons) and two coarse fuzzy ranges (ranges of energies and of spatial extensions of the atomic orbitals, AOs) characterize the atoms of the CEs and determine the two-dimensional structure of the PS. Concerning (iii), some relevant ‘facts’ about and from quantum chemistry are reviewed and compared with common ‘textbook facts’. What counts in chemistry is the whole set of nondiffuse orbitals in low-energy average configurations of chemically bonded atoms. Decisive for the periodicity are the energy gaps between the core and valence shells. Diffuse Rydberg orbitals and minute spin–orbit splittings are important in spectroscopy and for philosophers, but less so in chemical science and for the PS. (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)

Over the last half century, a multijurisdictional, multiscale system of governance has emerged to address concerns associated with toxic chemicals that have the capacity to bioaccumulate in organisms and biomagnify in food chains, leading to fish consumption advisories. Components of this system of governance include international conventions, laws enacted by nation states and their subjurisdictions, and efforts to adaptively manage regional ecosystems. Given that many of these compounds – including mercury, industrial chemicals such as polychlorinated biphenyls, and pesticides such as (...) toxaphene – circulate throughout the globe through cycles of deposition and reemission, regional efforts to eliminate the need for fish consumption advisories cannot be successful without efforts to reduce emissions everywhere in the world. This paper argues that the scientific community, by monitoring the concentrations of these compounds in the atmosphere and by modeling their fate and transport, play an important role in connecting the various jurisdictional scales of governance. In addition, the monitoring networks that this community of scientists has established can be visualized as a technology of governance essential in an era in which societies have the capacity to produce and release such chemicals on an industrial scale. (shrink)

The project of chemistry to classify substances and develop techniques for their transformation into other substances rests on assumptions about the means by which compounds are constituted and reconstituted. Robert Boyle not only proposed empirical tests for a metaphysics of material corpuscules, but also a principle for designing experimental procedures in line with that metaphysics. Later chemists added activity concepts to the repertoire. The logic of activity explanations in modern times involves hierarchies of activity concepts, transitions between levels through non-dispositional (...) groundings. Such hierarchies terminate in powerful particulars, such as elementary charged particles. Do these have a fundamental place in the most recent accounts of molecular architecture, stabilities and transformations? However, a close study of the contemporary chemistry of substances transforming reactions discloses a hybrid metaphysics, making use of both the Boylean corpuscles and Faradayan fields. This is illustrated by an analysis of the metaphysics inherent in John Polanyi’s use of “chemoluminescence” to follow the formation of products in chemical reactions. A brief sketch of a resolution of the tension between the two metaphysical schemes is drawn from Niels Bohr’s radical metaphysics extended from the quantum realm proper to chemistry (and perhaps beyond). (shrink)

The historical development of the understanding of water is traced in the light of the development of the general concept of chemical substance. From the times of the earliest known ancient Greek philosophers, water has played a central role in the conception of the material constitution of the world. But it was Aristotle who developed the most sophisticated understanding of water to have come down to us from the ancients. He viewed it as part of an intricate and systematic (...) theory of chemical substance, which classified water as an element along with earth, fire and air. His view exerted a considerable influence on Arabic and European thinkers throughout the Middle Ages, and wasn’t successfully challenged until the eighteenth century. After Lavoisier, it was recognised that water, though unlike air a single substance and not a mixture, is neither an element nor always liquid. General features of chemical substances, distinguishing elements, compounds and mixtures, were elaborated in a general theory and harmonised with the mechanical features of matter towards the end of the nineteenth century. Finally, the continuous conception of matter underlying the Aristotelian view, which had been unsuccessfully challenged in the seventeenth century, was definitely overturned in the twentieth century, and the intricate microstructure of water was revealed. (shrink)

This seminal paper, which marks a turning point of the chemical revolution, is presented for the first time in a complete English translation. In this first half Lavoisier undermines phlogiston chemistry by arguing that his French contemporaries had replaced Stahl’s original theory with radically different systems that conceptualised the phlogiston principle in completely incompatible ways. He refutes their claims by showing that these later models were riddled with inconsistencies as to phlogiston’s weight, its ability to penetrate glass and its (...) role as a source of colour and odour in chemical compounds. (shrink)

A chemical compound in the form of graph terminology is known as a chemical graph. Molecules are usually represented as vertices, while their bonding or interaction is shown by edges in a molecular graph. In this paper, we computed various connectivity indices based on degrees of vertices of a chemical graph of indium phosphide. Afterward, we found the physical measures like entropy and heat of formation of InP. Then, we fitted curves between different indices and the (...) thermodynamical properties, namely, heat of formation and entropy. Curve fitting was done in MATLAB through different methods based on linearity and nonlinearity. Furthermore, we depicted our results numerically and graphically. These numerical systems may give an approach to concentrate on the thermodynamical properties of the compound design of InP at an exceptional level that will help understand the connection between framework measurement and these actions. (shrink)

For the success of their individual activities, everyone should be able to receive the latest professional information correlate its important elements of their own practical experience, ultimately, at least, to take effective additional training in special circumstances. This requires a rich and modern information field of state. The older generation of doctors is formed in the conditions that existed in the Soviet Union and the Soviet Ukraine. Then there were no unscientific or outright false materials. Unfortunately, in modern Ukraine practically (...) disappeared restrictive barriers anti-sciences to esoteric and the other discipline, which dramatically reduced the quality of our national information field and considerably complicated the activities of all medical areas and relevant sector of higher education. The information revolution has changed everything. IBM has invited 600 scientists to input a large amount of information from hundreds of modern science in an unknown volume database. Complex supercomputer and the database named "Watson". This is the first ever active integrator scientific knowledge. Watson won the race with a medical diagnosis in two groups of experts. We are confident of good prospects for scientific integrators and personalized medicine of the XXIst century. In the article the negative phenomenon widening gap between the practice of medicine and scientific discoveries is considered. It is increased the time interval between the formulation of ideas of new drugs before they spread to the network of pharmacies and hospitals. Once it had been weeks or months, now – 12-17 or more years. Earlier drugs in the form of simple chemical compounds or combination of substances from the environment were produced and used by the doctor. Nowadays everything is much more complicated that article demonstrated appeal to the information made available on the Internet for several days in mid-May 2016. It is noted that market competition in medicine and morality contradict the culture of the Ukrainian people. Therefore, the national medical education should develop the foundations of the Hippocratic Oath, traditions and use discoveries of modern science. (shrink)

DNA possesses a double nature: it is both an analog chemical compound and a digital carrier of information. By distinguishing these two aspects, this paper aims to reevaluate the legally and politically influential idea that the human genome forms part of the common heritage of mankind, an idea which is thought to conflict with the practice of patenting DNA. The paper explores the lines of reasoning that lead to the common heritage idea, articulates and motivates what emerges as (...) the most viable version of it, and assesses the extent to which this version conflicts with gene-patenting practices as exemplified by the U.S. regime. It concludes that the genome is best thought of as a repository of information to which humanity has a fiduciary relationship, and that on this view, the perceived conflict with gene-patenting largely dissolves. (shrink)

While the objects of olfaction are intuitively individuated by reference to the ordinary objects from which they arise, this intuition does not accurately capture the complex nature of smells. Smells are neither ordinary three-dimensional objects, nor Platonic vapors, nor odors. Rather, smells are the molecular structures of chemical compounds within odor plumes. Molecular Structure Theory is offered as an account of smells, which can explain the nature of the external object of olfactory perception, what we experience as olfactory objects, (...) and what determines the olfactory quality of smells by which we can demarcate the spatiotemporal boundaries of smells. (shrink)

There is consensus within the chemosciences that olfactory perception is of the molecular structure of chemical compounds, yet within philosophical theories of smell there is little agreement about the nature of smell. The paper critically assesses the current state of debate regarding smells within philosophy in the hopes of setting it upon firm scientific footing. The theories to be covered are: Naïve Realism, Hedonic Theories, Process Theory, Odor Theories, and non-Objectivist Theories. The aforementioned theories will be evaluated based on (...) their explanations of the (a) the olfactory quality of a smell, (b) smells as distal entities, and (c) our experience of smells as intentional objects. The paper concludes with a defense of Molecular Structure Theory that demonstrating its superiority in accounting for each of these three aspects of smell. (shrink)

Hylomorphists claim that substances—human beings, oak trees, chemical compounds—are compounds of matter and form. If a house is a substance, then its matter would be some bricks and timbers and its form the structure those bricks and timbers take on. While hylomorphism is traditionally presented as a theory of change, it only treats the coming-to-be and passing-away of matter-form compounds. But many hylomorphists understand forms to be entities in their own right, as parts or constituents of substances. So, a (...) neglected question arises: how, when, and from where do forms come to be? I take up the view of one prominent and representative hylomorphist, Kathrin Koslicki, and argue that she cannot answer these questions satisfactorily. I close with a proposal for an account of the generation of forms based on machinery many hylomorphists already accept, namely, causal powers, that points to a deflationary metaphysics of form. (shrink)

Most philosophers consider olfactory experiences to be very poor in comparison to other sense modalities. And because olfactory experiences seem to lack the spatial content necessary to object perception, philosophers tend to maintain that smell is purely sensational or abstract. I argue in this paper that the apparent poverty and spatial indeterminateness of odor experiences does not reflect the “subjective” or “abstract” nature of smell, but only that smell is not directed to particular things. According to the view defended in (...) this paper, odors are properties of stuffs. This view, motivated by several arguments grounded in the phenomenology of olfactory experience, explains in particular why odors appear to be located both in the air around our nose and in the objects from which they emanate. It also explains the power of smell in the task of discriminating chemical compounds. (shrink)

Electronegativity is a quantified, typical chemical concept, which correlates the ability of chemical species to attract electrons during their contact with other species with measurable quantities such as dissociation energies, dipole moments, ionic radii, ionization potentials, electron affinities and spectroscopic data. It is applied to the description and explanation of chemical polarity, reaction mechanisms, other concepts such as acidity and oxidation, the estimation of types of chemical compounds and periodicity. Although this concept is very successful and (...) widely used, and in spite of the fact that it is still subject to scientific investigations, neither a more than intuitive definition nor a generally accepted, logically clear and standardized quantification model has been developed. In the present work, electronegativity is presented and discussed with respect to its main conceptual and operational continuities and discontinuities. We try to analyze the epistemological status of electronegativity, conceived as a typical notion of chemical sciences. Under ‘epistemological status’ we subsume the issues of its reference, its historical persistence, and the relationship between its measurement and quantification. (shrink)

A topological index can be focused on uprising of a chemical structure into a real number. The degree-based topological indices have an active place among all topological indices. These topological descriptors intentionally associate certain physicochemical assets of the corresponding chemical compounds. Graph theory plays a very useful role in such type of research directions. The hex-derived networks have vast applications in computer science, physical sciences, and medical science, and these networks are constructed by hexagonal mesh networks. In this (...) paper, we determined the exact values of vertex-edge-degree-based topological descriptors for hex-derived networks HDN 1 p and HDN 2 p, which are generated by the hexagonal network of dimension p. (shrink)

This article will explore whether there are arguments for Aristotle's concept mixis which can aid our current discussions within the philosophy of chemistry. We remain troubled by the way and extent to which chemical substance in bulk can be identified with or reduced to the stability and structure of molecules, and whether these in turn can be identified with or reduced to elemental atoms and the quantum theoretical characterization of their electrons. Aristotle was as determined as we are to (...) think through the implications of substances comprised of constituents and to question their status in chemical compounds. (shrink)

It is arguably the case that olfactory system contains two senses that share the same type of stimuli, sensory transduction mechanism, and processing centers. Yet, orthonasal and retronasal olfaction differ in their types of perceptible objects as individuated by their sensory qualities. What will be explored in this paper is how the account of orthonasal smell developed in the Molecular Structure Theory of smell can be expanded for retronasal olfaction (Young, 2016, 2019a-b, 2020). By considering the object of olfactory perception (...) to be the molecular structure of chemical compounds composing odor plumes, Molecular Structure Theory provides a means for determining an odor’s olfactory quality, how odors can be identified and individuated, and how we perceive smellscapes. Surveying the differences between orthonasal and retronasal olfaction provides the basis for the central argument of the paper that the perceptible objects we refer to as smells and individuated on the basis of their olfactory qualities are only relative to orthonasal olfaction. Retronasal olfaction it is speculatively concluded might play an essential role in our perception of flavorful objects. (shrink)