The Molecular Nature of Matter

Silberberg, M. S. (2006). Chemistry The molecular nature of matter and change (4th ed.). New York McGraw-Hill. 

The entire universe is made up of matter, from the vast reaches of the galaxies to a simple glass of water. As we describe in the coming chapters, matter is composed of tiny particles called atoms. On Earth there are around 100 different kinds of atoms, each kind with its own unique combination of properties. The complexity of our world arises from the unlimited number of ways that atoms can combine to form different molecules. The principles of modem chemistry are organized around the molecular nature of matter. Our book presents this perspective while at the same time emphasizing the quantitative aspects of chemistry. 

Silberberg, Martin S. 2006. Chemistry The Molecular Nature of Matter and Change, 4th ed. New York McGraw-Hill. 

The McGraw-Hill Companies, Inc. 172 (top). From Chemistry The Molecular Nature of Matter and Change. 2000, The McGraw-Hill Companies, Inc. 179 (bottom). From Chemistry The Molecular Nature of Matter and Change. 2000,... 

Sevenair, J.R, Burkett, A.R., Introductory Chemistry. Investigating the Molecular Nature of Matter. WCB Publishers, USA 1997... 

Jean Perrin s 1913 monograph, Les Atomes, on Brownian motion and some of the related topics on the molecular nature of matter has been reprinted recently (Perrin 1990) and is an interesting source of information on the evolution of ideas on diffusion and determination of Avogadro s number. This monograph also contains some of Perrin s sketches of random walks executed by colloidal spheres in his experiments. 

In the formulation of the microscopic balance equations, the molecular nature of matter is ignored and the medium is viewed as a continuum. Specifically, the assumption is made that the mathematical points over which the balance field-equations hold are big enough to be characterized by property values that have been averaged over a large number of molecules, so that from point to point there are no discontinuities. Furthermore, local equilibrium is assumed. That is, although transport processes may be fast and irreversible (dissipative), from the thermodynamics point of view, the assumption is made that, locally, the molecules establish equilibrium very quickly. 

Furthermore, one has to bear in mind that relating energy with temperature implies the consideration of the Boltzmann s constant, k. However, this natural constant will play a role in a physical problem only if the molecular nature of matter is involved, otherwise it is irrelevant. 

Though thermodynamics does not require us to invoke the molecular nature of matter it is frequently helpful to do so. It is particularly helpful in the distinction between heat and work. Work may be regarded as the energy associated with orderly movements of bodies, or the particles that comprise them, for example pushing back boundaries. Movements of centre of mass or... 

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