Foundations of Chemistry最新文献

In this paper we will argue that the identity of the entities that inhabit the nanoworld is a contextual identity. To defend that, we will analyse the so-called “biological” identity and the “synthetic” identity of nanomaterials. From this analysis, we will claim that nano-individuals (entities that show an intermediate nature between individuals and stuff), can be adequately understood from the perspective of a processual ontology. With that, we intend to contribute to the philosophical understanding of the ontology of the nano-domain.

In recent years, the definition of mole, the unit of the amount of substance, has changed to have the base units of the International System defined by “explicit-constant” formulations. The old definition, by referring explicitly to both mass and elementary units, suggests that the mole is a bridge between the macroscopic and microscopic registers. Conversely, the new definition emphasizes the aspect of counting, referred to any kind of elementary unit. Paradoxically, this results in the disappearance of the notion of substance from the very unit of the quantity amount of substance. This change of definition elicited both positive and negative remarks from various authors, in relation to its epistemological, disciplinary, lexical and educational implications. In the present paper, we analyze some of these issues, highlighting the (conflicting) motivations of metrologists and chemists. We argue that the new definition of mole reflects a view of chemistry according to which the microscopic perspective prevails, possibly entailing the loss of reference to the macroscopic register; this could be related with the profound change undergone by the cognitive practices of chemistry along this last century.

Although the electron density can be calculated with the formal resources of quantum mechanics, in physics it does not play the leading role that the quantum state does. In contrast, the concept of electron density is central in quantum chemistry. There is no doubt about how the electron density is computed in terms of the wave function of an atom or molecule. However, when the interpretation of the concept is at stake, there is no general agreement. In this article we will analyze the two main interpretations of the concept of electron density: the Born-style probability density interpretation and the Schrödinger-style charge density interpretation. In particular, we will examine their differences, their relations with quantum mechanics and the consequences that each of them entails from a strictly quantum point of view.

In this paper, we will address a recurring problem in the field of the general philosophy of science but one that takes on particular relevance in the context of chemistry: the problem surrounding scientific laws. The main challenge is that the laws of chemistry are not universal; moreover, in practice, they are stated alongside numerous exceptions. Given that there are exceptions, we could argue that what the laws assert is neither universally true nor necessary. But if that's the case, are they genuine scientific laws? And if so, what is the reason for such lawfulness?

The meaning of the once widely used term the Gibbs Free Energy in terms of available work energy is perfectly illustrated for chemical reactions by the Van’t Hoff Equilibrium Box. Combining this with DeDonder’s extent of reaction variable and using the reaction of (hbox {NH}_3) to (hbox {H}_2) and (hbox {N}_2) at (200^{circ }hbox {C}) as an example shows the difference between total work energy and available work energy, and in addition allows calculation of the equilibrium composition, demonstration of the minimum in the Gibbs energy curve, and the standard relationship between (Delta _textrm{r}G^{circ }) and (ln {K})

There are 2 main problems with the current periodic table: artificial breaks from a given noble gas to the next alkali metal (along with the common protrusion of the “f” block) and hydrogen placed in the alkali group, although this gas also exhibits halogen properties. This paper proposes arranging chemical elements in a square spiral with hydrogen at the centre. This element is also above lithium but passes above fluorine to connect with helium, representing its dual alkali and halogen nature effectively. Then the spiral moves outwards in a counter-clockwise direction, avoiding artificial breaks and following the natural direction of reading for the “s” and “p” blocks elements placed at the bottom of the spiral. Furthermore, this proposed square spiral improves upon previous Janet´s and Benfey´s representations with a more regular shape to draw, an effective depiction of the dual nature of hydrogen, and easily identifiable orbital blocks without the need for protrusions.

Franklin and Seifert (2021) argue that solving the measurement problem of quantum mechanics (QM) also answers a question central to the philosophy of chemistry: that of how to reconcile QM with the existence of definite molecular structures. This conclusion may appear premature, however, because interactions play a crucial role in shaping molecules, but we generally lack detailed models of how this is accomplished. Given this explanatory gap, simply choosing an interpretation of QM is insufficient, unless the interpretation also has relevant conceptual resources that address how spatially organized molecules are composed. This article seeks to close the gap, using the interpretation provided by relational quantum mechanics (RQM), along with a posited causal ontology. This framework, which entails the co-existence of multiple perspectives on systems within a single world, offers a path toward reconciling the quantum mechanical view of molecules with another conception more congenial to chemistry: that of molecules shaped by patterns of localizing interactions.

The theme surrounding scientific discoveries is quite neglected in and about the sciences, especially in terms of historical and epistemological understanding. Discoveries are often treated as simple information about dates, places, and people. This work presents discussions centered on historical episodes related to chemical elements and the Periodic Law, based on reflections by Thomas Kuhn and Norwood Hanson, aiming to highlight and contextualize specific scientific discoveries' conceptual and epistemological structure. With that in mind, issues related to the inseparability of the contexts of discovery and justification are recovered, along with the complex intrinsic structures of the genesis of scientific knowledge and distinct types and categories of scientific discoveries.

In this paper, we present a bibliometric analysis of the Periodic Table. We have conducted a comprehensive analysis of Scopus based database using the keyword “Mendeleev Periodic Table". Our findings suggest that the Periodic Table is an influential topic in the field of Inorganic as well as Organic Chemistry. Areas for future research could include on expanding our analysis to include other bibliometric indicators to gain a more comprehensive understanding of the impact of the Periodic Table in the chemistry-based scientific investigations and even in the field of astrochemistry, which explores chemical processes in space, is intricately linked to fundamental chemistry. In this context, the quote of Carl Sagan is relevant where he eloquently expressed an inherent connection between chemistry and astrophysics: “The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars.” In the ongoing study we have presented a ground level investigation of the conjecture of Sagan via Periodic Table based on bibliometric analysis whereas in the next level our aim is to present the stellar connection of it through Hertzsprung-Russel diagram as well as cluster of stars. The Periodic Table holistically serves as a foundational platform for understanding chemical elements both on the Earth and in celestial bodies. The present investigation fundamentally identifies the main working field of research and lays the groundwork for potential connections to astrochemical studies.