Open AccessThe potential difference occurring in a Donnan equilibrium and the theory of colloidal behaviour
Publication year - 1923
Publication title -
proceedings of the royal society of london. series b, containing papers of a biological character
Language(s) - English
Resource type - Journals
eISSN - 2053-9185
pISSN - 0950-1193
DOI - 10.1098/rspb.1923.0017
Subject(s) - colloid , basis (linear algebra) , hydrogen ion , ion , thermodynamics , colloidal particle , membrane , donnan potential , chemistry , chemical physics , physics , mathematics , organic chemistry , biochemistry , geometry , electrode , electrolyte
It is contended by Loeb that the Donnan Membrane Equilibrium, involving the presence of an indiffusible ion, is the basis of the colloidal properties of a protein solution. While the possibility of this conclusion is admitted, it is pointed out that one of the chief arguments employed in its favour by Loeb is incorrect. Loeb shows that the P. D. observed experimentally between a protein and a non-protein solution separated by a membrane agrees very exactly with that “calculated” from the difference in hydrogen-ion concentrations also observed experimentally, and concludes that this supports his theory. As a matter of fact, this equality is a necessary and inevitable consequence of the manner in which his observations were made and of general thermodynamical reasoning, and its proof is independent of any theory of the mechanism by which the P. D. is produced.