382 C. A. Peters — Eh ctroli/sis of Sodium Chloride 



was "0005 grins., an amount analytically negligible. These 

 experiments are written in Part 4 of Table V. 



In another group of eight experiments made, as always, with 

 freshly distilled mercury — those recorded in Table VI — done 

 under practically the same conditions as those mentioned in the 

 previous paragraph, part of the mercury yielded -0009 grins, 

 of silver. Part of the globule of mercury containing all the 

 silver was spilled just before the final heating but not more 

 than one-quarter was lost. Allowing for this loss and calling 

 the actual amount of silver "0011 grms., the amount of silver 

 transferred to the cathode is proportionately the same as in the 

 four experiments of the previous paragraph — "0001 for each 

 electrolysis — and also small enough to be neglected. 



Further, as shown in Part 5 of Table V, four electrolyses 

 were made similarly, except that the current was interrupted 

 when the ammeter read - 2. The mercury upon distillation 

 yielded "0001 grms., an amount of silver easily visible in a 

 porcelain crucible and which was precipitated as the chloride 

 with sodium chloride after solution, evaporation to dryness and 

 re-solution. The decomposition of the sodium chloride in the 

 inner cell was not complete under these conditions, as amounts 

 varying from 8 to 30 mgrms. were found by titration of the 

 inner cell liquid. 



These facts show the transfer of silver from the plated anode 

 to the mercury to be a regular feature of the electrolysis, under 

 the conditions described in this paper, and that the amount of 

 silver so transferred is considerably increased if the electroly- 

 sis is continued beyond the point where the sodium chloride is 

 all decomposed ; but if the electrolysis is interrupted as soon as 

 the salt is all decomposed very little silver is transferred to the 

 mercury. 



Using a Silver Anode. — Next the silver plated platinum 

 anode was substituted by one of pure silver with the same 

 general result, although the size and shape of the silver anode 

 were decidedly different from the plated platinum one previ- 

 ously used. 



This silver anode was made by wrapping a piece of gauze* 

 10x6 cm around a 20 mm test tube shortened in length to 5'5 cm . 

 A couple of sharp glass points on the outside of the test tube 

 held the gauze in position and a silver wire wrapped around 

 the top of the tube secured the gauze firmly as well as furnished 

 connection with the metal rod above, onto which the rubber 

 stopper and, in turn, the test tube, fitted. The amount of 

 gauze dipping into the electrolyte during the experiment was 

 about l - 5xlO cm , making the surface of anode metal exposed 

 much less than in the two previous experiments with the silver 



* A German article copper free. 



