L'osmose ; Dilution entropique

<div>ABSTRACT The selective transport of particles across a membrane separating two solutions with different solute concentrations is called osmosis. Osmosis occurs in many situations in biology, chemistry, and other fields. It plays a fundamental role in biology, where it determines the equilibria of biological systems, both animal and plant. It can be described as the movement of a system toward its thermodynamic equilibrium. It is essential for those working in these fields, as well as for the teachers who train them, to have an intuitive and straightforward understanding of these phenomena. Although osmosis is thoroughly explained in thermodynamics textbooks, students often remain dissatisfied, with the impression that they have not grasped the phenomenon described as osmotic pressure. Here, we argue that the very notion of "osmotic pressure" is problematic and that this terminology should be abandoned. We propose replacing it with "Entropic Dilution", or "Entropic Stress". To facilitate understanding, we use the statistical approach to thermodynamics. In this approach, osmosis naturally appears as a consequence of the second law of thermodynamics, which governs the irreversible time evolution of isolated physical systems. This choice allows us to describe the process in detail and identify the underlying mechanisms. </div>