498 



SCIENCE. 



[N. S. Vol. XX. No. 511. 



I have the theory of electrons in mind. 

 The ingenious experiments of J. J. Thomp- 

 son have given us considerable reason for 

 thinking that the negative electrons are ca- 

 pable of an independent existence and have 

 also given a probable estimate of their 

 mass, which is small in comparison with the 

 mass of the hydrogen atom. 



It has been customary to think of the 

 unit charge of electricity as being involved 

 only in those reactions which occur in solu- 

 tion. If, however, we accept the theory of 

 electrons it is evident that the electrons 

 must be present in the molecule of an elec- 

 trolyte no matter in what manner it is 

 formed. It is but a step further to the con- 

 clusion that the electrons are involved in 

 every combination or separation of atoms 

 and, indeed, may be the chief factor in 

 chemical combination. 



Professor Kahlenberg* has shown that a 

 practically instantaneous reaction takes 

 place between hydrochloric acid and cop- 

 per oleate in a solution in dry benzene, 

 although the solution does not conduct an 

 electric current and there is no evidence 

 of the dissociation of either the copper 

 oleate or of the hydrochloric acid. Pro- 

 fessor Kahlenberg points out very justly 

 that there is no apparent difference between 

 these reactions and those which take place 

 in aqueous solutions, where we have much 

 independent evidence of the existence of 

 ions. He draws the conclusion that no ions 

 exist in either case. It would seem that we 

 are equally justified in supposing that a 

 substance not already in the form of ions 

 may separate into them under the influence 

 of a second substance with which it can 

 react. 



Some time ago Mr. Lyon and myselff 

 showed that the primary reaction between 

 chlorine and ammonia gives nitrogen tri- 

 chloride, nitrogen and hydrochloric acid, 



* J. Phys. Chem.., 6, 1. 



t J. Am. Chem. Soc, 23, 460. 



and that these products are formed in such 

 proportion as to lead to the conclusion that 

 three molecules of ammonia react simul- 

 taneously with six molecules of chlorine. 

 It was pointed out at the time that the sim- 

 plest explanation of this result is to be 

 found in supposing that chlorine atoms sep- 

 arate during the reaction into positive and 

 negative ions, while the ammonia separates 

 partly into positive nitrogen and negative 

 hydrogen and partly into negative nitrogen 

 and positive hydrogen.* This hypothesis 

 has met with some approval,! but has also 

 received the criticism that such a dissocia- 

 tion as is supposed would result in the spon- 

 taneous decomposition of ammonia into ni- 

 trogen and hydrogen.^ This criticism 

 loses its force if we suppose that the separa- 

 tion into ions takes place only under the 

 immediate influence of the chlorine with 

 which the ammonia reacts. It has been 

 pointed out by many different authors§ that 

 a separation of atoms from each other must 

 occur either before or at the same time that 

 they enter into combination with other 

 atoms. The only part essentially new in 

 the hypothesis proposed is that this separa- 



* This was represented graphically thus : 



t Stuglitz, J. Chem. Soc, 23, 707. 

 t Ztschr. Phys. Chem., 41, 378. 

 § See Erlenmeyer, Jr., Ann. Chem. 

 316, 50. 



(Liebig), 



