JACQXJES LOEB 



185 



When we render Na2S04 solutions acid (by dissolving the salt in 

 m/128 or m/1,024 HNO3) the negatively charged particles of water 

 diffusing through the membrane will be repelled by the SO4 ion and 

 attracted by both the Na and H ions. Since the SO4 ion carries two 



240 



220 



200 



180 



IGO 



140 



120 



100 



80 



60 



40 



20 



O 



O 



-3 







4036 2048 1024 512 256 128 64 32 16 8 4 T ^^ ^ 



Concentration 



Fig. 7. Upper two curves representing influence of acid solutions of CaCl2 

 or of Ca(N03)2 upon negatively charged particles of water. At first there is a 

 steep rise of the curve due to prevalence of attraction of Ca for the negatively 

 charged particles of water, then beyond m/64 a drop in the curve due to prev- 

 alence of repeUing action of NO 3 and CI upon the negatively charged particles of 

 water. No initial rise in the three lower curves, since in neutral and alkaline 

 solutions of Ca water diffuses in the form of positively charged particles which 

 are too strongly repelled by Ca to permit an initial rise in the level of the solution. 



charges while the cations Na and H are monovalent the greater elec- 

 trostatic action of the SO4 ion should inhibit the electrostatic attraction 

 of water by such solutions in the same way as is done by neutral so- 



