626 



have been determined only for As^S, ^) and HgS, *) and for electro- 

 lytes not used here. 

 The proportions are : 



With As.Sj XNH4C1 : Xuo./N03)2 = 82 



HgjS XXII4CI : XBaBr, =^ 29. 



The proportion chosen 60 : 1 is, tiierefore, a rough approximation, 

 but a comparison with y-valiies of other sols [Pt, Au etc.) renders 

 it probable that it represents the average. 



The relations between charge, adsorption and limit value are 

 elucidated schematically in the above figure. In the upper half of 

 the figure is drawn the charge e of tlie capillary in dependence on 

 the concentration of the traversing liquid, so that I, 11, and III stand 

 for uni-, di- and trivalent cations respectively. In the lower half is 

 given, with the same concentration axis, the correlated adsorption 

 of the electrolyte as a downward directed ordinate. If now Xu X2 

 and X3 indicate the relation of the limit values for uni-, di- and 

 trivalent catious, respectively the correlated downward directed ordinates 

 must show the proportion 1 : 1^ : 3 and the upward directed ones 

 equal values. 



4. For verilication of this relation appeared suitable : 



{a) 10 ^cMol BaCl, — 600 .uMol KCl. 



b) 25 jfiMol BaCl, — 1500 j.Mol KCl. 



It would not do to simply take the specific conductivity powers 

 as being proportional to the concentrations because in the so strongly 

 diluted BaClj solutions the conductivity power of water could not 

 be neglected. Hence, 1 have made a direct measurement of the 

 relation of llie specific resistances by filling in Whkatstonk's bridge 

 a vessel of arbitrary but fixed capacity with the liquids used. 



The relation of these resistances was in the pair {a) 



and in the pair (/>) 



a>6 4630 ^^^ 



-— = — = iy 



w^- 247 



«^=2770^28 

 Oik 99.9 



E 

 The values of — are obtained from the research communicated 

 P 



in the preceding paper. 



1) Freundlich. Zeitschr. f. physik. Ghem. 73, SS5 (1910). 



2) Freundlich en Sghught, ibidem 85, 641 (1913). 



