82 



DONNAN EQUILIBRIUM AND VISCOSITY 



curves like those of Fig. 5, which are no longer straight lines as in 

 the case of crystalline egg albumin but curved lines. The curvature 

 is the smaller the higher the temperature. 



025 0.5 1.0 15 20 Z5 3.0 aS 40 



Concentration of gelatin in per cent 



Fig. 5. Influence of concentration on the viscosity of solutions of isoelectric gelatin. 



In these experiments the gelatin solution was first heated rapidly 

 to 45° and then brought rapidly to the temperature indicated in the 

 figure. The formula of Einstein can no longer be applied but the 

 formula of Arrhenius gives fair agreement 



Log — = d<p 



