JACQUES LOEB 



187 



neutral and alkaline solutions of Na2S04 upon the rate of diffusion of 

 positively charged water particles. 



It was finally expected that the curves representing the influence of 

 various concentrations of NaCl upon the rate of diffusion of water 

 through collodion membranes should be similar in neutral, acid, and 

 alkali solutions, for the reason that anion and cation of the salt are 



n nnriiirinnnnnii-|M2M 



4096 20® 1024 512 256 128 64 32 16 8 4 g " ^ ^' ' 



Concentration 



Fig. 9. Salts with monovalent anion and cation, like NaCl, show both rise and 

 drop in alkaUne, neutral, and acid solutions. In neutral and alkaline solutions 

 the first rise is due to the attractive action of the CI ion and the drop to the 

 repelling action of the Na ion upon the positively charged particles of water. 

 In acid solution the first rise in the curve is due to the attractive action of the 

 Na ion and the drop to the repelling action of the CI ion upon the negatively 

 charged particles of water. 



both monovalent (Fig. 9). In the presence of a sufficiently acid solu- 

 tion of NaCl the particles of water diffuse as negatively charged 

 molecules through the membrane which are attracted by the Na ions 

 and repelled by the CI ions. The initial rise of the curve is due to the 

 attractive action of the Na ion, and the drop in the curve is due to the 

 increasing prevalence of the repelling action of the CI ion. In neutral 



