In the following chapters and, indeed, throughout our further work, we shall continually meet additional instances of the quantitative relation between chemical activity and ionization. In fact, the results obtained in the field of quantitative measurement of chemical action, of which the above are single instances, have demonstrated, more than anything else, the value of the theory of ionization to chemistry and the necessity of taking it into account in expressing the results of chemical action in mathematical terms. [p083] «Summary.»—Measurements made, then, in three great and independent fields of investigation, ‹electrical conductivity›, ‹osmotic pressure› and the allied relations, and ‹chemical activity›, bring independent testimony to the correctness of the fundamental assumptions of Arrhenius's theory of ionization. In the quantitative study of solutions of electrolytes, wherever secondary disturbing influences are eliminated or are taken into account as far as possible, the three lines of investigation give results which agree satisfactorily[143] as to the degree of ionization of the electrolytes under examination. With the aid of this theory, ‹predictions› of the course of chemical action may now be made more definitely and with more assurance than ever before in the history of chemistry. «Chemical Activity of Non-ionized Molecules.»—The conclusion reached, on the basis both of qualitative and, particularly, of quantitative evidence, that the reactions of salts, acids and bases (ionogens) in aqueous solutions (the so-called salt reactions) are the actions of the ions and not of the non-ionized molecules, does not necessarily mean that the non-ionized molecules are altogether inactive chemically. Some chemists believe that ions have only the advantage of an ‹enormously greater degree of reactivity›.[144] If the atoms in a molecule carry electric charges even prior to their separation (ionization), as expressed for instance by the formula H^{+}Cl^{−} for hydrogen chloride (p. 43), it can be readily seen that an action[145] resulting from the collision of a molecule of hydrogen chloride with a molecule of potassium hydroxide H^{+}Cl^{−} + HO^{−}K^{+} ⇄ K^{+}Cl^{−} + HO^{−}H^{+} would, in some respects, resemble the ionic action H^{+} + Cl^{−} + K^{+} + HO^{−} ⇄ K^{+} + Cl^{−} + HOH. The latter would probably have the advantage of a considerably smaller resistance to the action, and consequently of a far greater speed. ‹But the question of supreme importance and interest to chemistry is the question as to which actions are found experimentally to be of moment in any given case.› Now, a great mass of corroborative evidence shows that for the interactions of ionogens in aqueous solutions the ionic actions, probably on account of their enormous speeds, ‹are the important ones›. [p084]