154 Prof. Ostwald on Chemical Action at a Distance. 



of the nitric acid serves the purpose. As the latter is reduced 

 to nitrous acid, a bivalent oxygen atom, that is one with two 

 negative electrical charges, becomes free and, with two posi- 

 tive hydrogen ions, forms water. Thereby two metal ions 

 with their corresponding positive charges can enter the liquid, 

 or, in other words, are forced thereto by the excess of nega- 

 tive ions now contained in the liquid. The electricity remain- 

 ing in the metal compensates the positive electricity, w T hich, 

 according to the general law of the " Conservation of Elec- 

 tricity," must be developed upon the separation of the negative 

 oxygen atom. It can scarcely be necessary to add that all the 

 quantities of electricity in question are, by Faraday's law, 

 exactly equal to one another. 



Finally, the question presents itself whether galvanic cur- 

 rents may not also be developed in aqueous solutions without 

 the help of any metal, only by means of formation and de- 

 struction of ions. Let us consider a liquid which has the 

 capacity of developing positive ions, and a second in contact 

 with it which can create negative ions (or destroy positive 

 ones) ; then the actions will again occur with especial readi- 

 ness when care is taken that the corresponding quantities of 

 electricity be conducted away. This is effected by the inser- 

 tion of conductors of the first class, which are not chemically 

 attacked, and which are connected so as to make possible a 

 reciprocal neutralization of the displaced quantities of elec- 

 tricity. 



This case becomes realized when we bring, for example, a 

 solution of ferrous chloride in contact with one of sodium 

 chloride containing free chlorine, and dip in both solutions 

 connected electrodes of carbon or platinum. The bivalent 

 ferrous ions in the ferrous chloride change into trivalent ferric- 

 ions. The negative quantity corresponding to the positive 

 electricity is discharged through the electrode into the chlo- 

 rine solution, and supplies there the amount of electricity 

 necessarv for the change of the molecular chlorine into 

 chlorine ions, and this action continues until the supply of 

 ferrous ions or chlorine molecules is exhausted. 



It becomes at once clear that here we have again to do 

 with a chemical "Action at a distance " of the above-described 

 kind. For it plainly makes no difference as to the action 

 whether the solutions of ferrous chloride and of chlorine are in 

 immediate contact, or are separated from each other by any 

 electrolyte, as for example sodium-chloride solution. For 

 since the transfer of electricity takes place from and to the 

 ions of the electrolytes, the ferric chloride is formed in this 

 case not directly from the chlorine-water but at the submerged 



