Anderson. — Electrical Deposition of Nickel. 



507 



Results. 



Time. 



Hours. 



! l 



(a.) One equivalent of ammonium nitrate - 2 



I 3 



1 

 (6.) Two equivalents of ammonium nitrate -j 2 



3 



(c.) Experiment with ammonium nitrate 

 alone 



Series 5. 



1 



2 



Amou ill 



Hydro xyla mine. 



Grammes. 



0-059 



0-033 



0-008 



0-050 

 0-023 

 0-007 



0-093 

 0-035 



The preceding series of observations indicates that though hydroxylamine 

 is undoubtedly a product of the reduction, yet it undergoes further change 

 subsequent to its formation- — probably being reduced to ammonia. The 

 formation of hydroxylamine, however, can only be ascribed to reduction 

 taking place at the cathode ; and in order to study more closely this action 

 it was decided to conduct a series of experiments in a divided cell where 

 the anode and cathode compartments were kept separate, so that the 

 solutions could be analysed separately. 



Apparatus. 



The apparatus consisted of a Grove porous pot and outer vessel ; the 

 inner compartment contained the same solution as in the previous cases — 

 one-third quantities being used — and in it was placed the cathode. The 

 outer vessel contained ammonia and ammonium sulphate solution. 



Results. 



(a.) No nitrate present . . 



Time. 

 Hours. 



11 



(b.) One equivalent ammonium nitrate . . 9 



il 



(c.) Two equivalents ammonium nitrate . . -■ _ 



11 



(r/.) Three equivalents ammonium nitrate 



Amount of hydroxylamine 



Time. 



Hours. 

 il 



• 12 



Amount 



deposited. 



Grammes. 



0-0540 



0-0686 



0-056 

 0-068 



0-054 

 0-066 



0-053 

 0-063 



Amount 



formed. 



Grammes 



0-037 



0-008 



Discussion. 



The results obtained with the divided cell were certainly more satis- 

 factory in the presence of the nitrate, and seemed to indicate that increasing 

 amounts of the nitrate did not produce such a decided effect on the rate 

 of deposition as when the undivided cell was used. This would seem to 

 suggest that perhaps some product formed at the anode had the effect of 

 retarding the progress of the electrolysis. 



