508 Transactions. 



There appears to be no doubt that the hydroxylamine undergoes a 

 further change. An experiment was performed as follows to test this : — 



Experiment. 



To the solution in the cathode compartment, containing no nitrate, 

 were added successive quantities of hydroxylamine so as to produce con- 

 ditions as nearly comparable as possible to those that would be expected 

 to obtain from the basis of Faraday's law. Suppose, for instance, one equi- 

 valent of ammonium nitrate were present ; then the amounts of hydroxyl- 

 amine present in the solution at various times — e.g., J hour, | hour, &c. 

 — -can be approximately computed. At intervals, then, such amounts of 

 hydroxylamine were slowly added. It is at once apparent that the condi- 

 tions in the two cases are by no means identical, for in one a certain amount 

 of energy is expended in producing the hydroxylamine prior to its trans- 

 formation, while in the other such an expenditure of energy is not involved. 

 Hence, while one would expect to be able to isolate a greater amount of 

 hydroxylamine in the latter case, yet a comparison of the results in the 

 two cases was considered likely to prove instructive. This was repeated, 

 and good agreement in each case was found. The results of one set of 

 this experiment may be given as typical : — 



, T ., Hydroxylamine 



Nitrate present. J , r , 



Grammes. Grammes. 



Nickel deposited .. .. .. 0-056 0-056 



Hydroxylamine .. .. .. 0-037 0-041 



Series 6. 



The results of the previous experiments indicated that energy [was 

 primarily utilized in the formation of hydi-oxylamine. It was, however, 

 considered possible that nitrous acid might be formed as an intermediate 

 substance according to equation 1, swpfa. Were this the case it was thought 

 that some substance might be introduced which by chemical interaction 

 would destroy the nitrous acid and convert it into harmless products, without 

 otherwise interfering with the course of the electrolysis. This would tend 

 to accelerate the removal of the nitrate, and would enable the electrical 

 energy to be utilized more completely in effecting the deposition of the 

 nickel. 



The obvious desirability of introducing a substance that would not 

 exert an effect upon the electrolyte and at the same time interact with the 

 nitrous acid (if formed) suggested the use of urea. 



Result. 



The solution in the cathode compartment then was rendered faintly 

 acid and the experiments conducted as before. The mean of a number of 

 closely agreeing values gave at the end of one hour — 



AT TT Urea added — Acid 



No Urea. <-, , ,. 



(solution. 



Grammes. Grammes. 



Amount nickel . . . . . . 0-056 0-055 



Amount hydroxylamine . . . . 0-037 0-038 



This apparently indicated that nitrous acid is not formed as an intermediate 

 product. 



