Rapport Du Comite Consultatif; Report of the Advisory Committee Volume 4 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1896 edition. Excerpt: ...time, and, during the rest of their existence, they are incapable of moving forward. We shall find other indications, both from chemical and from osmotic pressure phenomena, that, at any instant, a certain number of the molecules differs from the rest in condition, and the same number as we deduce from the conductivity is indicated by these two effects. Various hypotheses might be framed in order to explain the physical difference between the active and inactive molecules. The most important of these is that due, in the first place, to Arrhenius. who supposes that an electrolytically active molecule is dissociated into its ions. We might, however, as far as we have yet gone, imagine that the necessary condition for electrolytic activity was a certain temporary arrangement of the atoms in the molecule, or that two molecules could interchange their ions only when they collided in a certain definite way. Let us, then, for the present, call the state of activity of a molecule ionisation, and not use the word dissociation, which commits us to one hypothesis. It is evident from what has been said, that the ionisation of a solution of a certain strength (1.e., the fractional number of its molecules electrolytically active at any moment) is measured by the ratio of its molecular conductivity to the molecular conductivity of a solution of the same substance at infinite dilution, when all the molecules are active. Thus, if we denote the molecular conductivity by the symbol j1, and its value at infinite dilution by nx, we get for n, the coefficient of ionisation, the value n Pm. In the year 1883, Arrhenius published a paper1 in which he showed that this coefficient of ionisation was intimately connected with the chemical activity of the solution, ..