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IX. On the Nature of Chemical Force and the Anomaly 

 of Strong Electrolytes, By William Hughes, B.Sc. 

 (Oxon.), M.A* 



IN an aqueous solution of volume Y of an electrolyte CA 

 whose degree o£ ionization is a, the concentrations of 

 the ions are respectively a/V, and of the undissociated 

 molecules (1 — a)/V. The constant of the equilibrium repre- 

 sented by the chemical equation, 



is, as Ostwald first showed, according to the Law of Ma«s 

 Action given by the relation, 



K 



(l-a)V 



According to this law the rate of each reaction is equal to 

 the product of its velocity constant and the concentrations 

 of the reacting substances, at the same temperature and 

 pressure. K is the ratio, therefore, of the velocity constant 

 of ionization to that of the recombination of the ions. It is 

 well known that for highly ionized substances K varies 

 widely with the concentration, being as a rule larger the 

 higher the concentration. 



Of the many attempts which have been made to account 

 for this anomaly of strong electrolytes, none take into con- 

 sideration the possible heterogeneous nature of the chemical 

 forces operative in the system. The electrical forces between 

 ions of opposite sign in all probability do not make up all 

 the attractive force. For example, from LangnnuVs theory 

 of the "cubical" atom, the only difference between an ion of 

 chlorine, an atom of argon, and an ion of potassium, is that 

 they have respectively 17, 18, 19 positive charges on the 

 atomic nucleus. Each one has 18 electrons, so that 

 the chlorine ion is electrically negative, the potassium 

 positive, and the argon atom neutral. Now, since there 

 exist cohesive forces between argon atoms, it appears highly 

 probable that such forces exist between the potassium and 

 chlorine ions, quite apart from the electrical forces. It 

 w r ould appear that the greater these cohesive forces between 

 two ions, the less ceteris paribus the degree of ionization, as 

 in the case of weak electrolytes and, at the end of the scale, 



* Communicated by tlie Author. 



