1021 
would be smaller than for the movement under constant force. The 
observations are too rough for quantitative caleulations, but the 
differences of mear. ANd Meas, are too great and too much in one 
direction to be attributed to errors of observation. 
Amsterdam. Physical Laboratory. 
Chemistry. — “Current Potentials of Electrolyte solutions.” (Second 
Communication). By Prof. H. R. Kruyr. (Communicated by 
Prof. Ernst Coney). ’ 
(Communicated in the meeting of January 27, 1917.) 
1. In a former paper’) I communicated a series of measurements 
with respect to the influence of dissolved salts on the current 
potential, after having made investigations with solutions of the 
chlorides of potassium, barium and aluminium. These salts were 
chosen, because they are electrolytes with resp. a monovalent, a bivalent 
and a trivalent cation. In Tables 2 and 3 similar results are given 
for investigations made with hydrochloric acid and the chloride of 
p-chloro-anilene. A standard solution of HCl was prepared by 
conducting gaseous hydrochloric acid in “conductivity water”; to get 
the solution of p CIC,H,NH,.HCl KarrBaum’s pClC,H,NH, was 
dissolved in water containing the equivalent. quantity of HCl from 
the solution first mentioned. 
The results given in Tables 2 and 3 show the decrease of the 
current potential to be here much larger than in the case of potas- 
siumchloride (cf. Table 1, columns 1 and 2). This result is in perfect 
agreement with the investigations on electric endosmosis (for litera- 
ture, see my first communication), and it can be easily understood 
when we suppose, as FRrEUNDLICH does, that these phenomena are 
in close relation with the adsorption of the ions: the H-ion, and 
also the organic ions (especially aromatic ones) are adsorbed in a 
greater amount than those of the light metals. A comparison of 
Tables 2 and 4 shows, that the monovalent H-ion and the bivalent 
Ba-ion bring about nearly the same lowering of the current 
potential. 
2. A comparison between the electric charges of the capillary 
tube is still of more importance than that of the current potentials 
especially with regard to the problems of colloid-chemistry ’). 
1) These Proceedings 17, 615 (1914). 
2) See H. R. Kruyt, These Proceedings 17, 623 (1914), 
oS 
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Proceedings Royal Acad. Amsterdam. Vol. XIX. 
