Vol. VI, No. 2.1 



■/ 



47 



have become concave after an inflexion. With prolonged 

 electrolysis, however, the fall became gradually smaller and 

 smaller till at last the values tended to become more or less 

 stationary, as the last part of the curve would indicate. 



With 



rate 



of rise is more gradual and much smaller throughout 

 than that for the fall of the cathode equivalent. It is interest- 

 ing to note how the observed values of the e.c.e. both for 

 cathode and anode tended to equalize with repeated electro- 

 lyses, the former coming down by rapid steps and the latter 

 going up more slowly but steadily. For instance, at the end 

 of the first experiment the e.c.e.'s for cathode and anode arc 

 0002906 and -0000147; while at the end of the last deter- 

 mination they were found to be -0000597 and -0000488 

 respectively ! 



It is difficult to understand the sudden drop in experiment 

 3, Table I. The deposit obtained was good, so that there 

 was no loss of weight at the time of washing. It could, 

 however, be explained on the hypothesis that it was only due 

 to the effect of accumulation of acid developed in previous 

 experiments in the part of the solution lying between cathode 

 and anode. In all subsequent experiments the solution was 

 thoroughly stirred before the current was started. To investi- 

 gate whether this sudden drop was accidental, the following 

 set of observations were made with a fresh quantity of the 

 same volume (160 c. c.) of neutral solution (specific gravity 

 different). The current was passed for only five minutes at a 

 time in order to examine the steps of fall more closely. The 

 results are tabulated below : 



Table III. 



Effect of successive Electrolysis for small 



Total time. 

 Second. 



Current 

 ( Amp. ) 

 Actual. 



Current 



(Amp.) 

 Mean. 



Ca. Gain 

 (Grm.) 



Total Ca. E.C.E. E.C.E 



Gain 

 (Grm.) 



(Ca.) 

 7 x 1 0-7 



(C.) 

 Mean. 



xio-7 



300" 



600" 



900" 



1200" 



1 500 " 



1800" 

 2100" 



2400" 

 2700" 



3000" 



•07<;s 



0697 



•0718 



1688 



0599 



060 4 

 0522 

 '398 

 0373 

 0325 



•0768 

 1464 



28 70 

 •3469 



•4073 



1594 



•4! '93 



•5365 



i690 



2997 

 8878 



2739 

 !564 



2255 

 2188 

 1962 

 14. -.9 

 1427 

 1240 



2997 



-'93 7 



286!' 

 2789 

 2*-75 

 268! 



249 

 2364 

 2261 

 2160 



grad 



