100 



ION SERIES AND PROTEINS. 



The results can be given briefly. Fig. 9 gives the curves for the cc. 

 of 0.1 N HNO3, H2SO4, oxalic, and phosphoric acids required to bring 

 1 gm. of isoelectric gelatin to different pH. The curve shows again 

 that for each pH the number of cc. of 0.1 n acid required are forHNOa, 

 H2SO4, oxalic, and phosphoric acids approximately as 1:1:2:3. 



pH 2.0 22 24 26 28 30 32 34 3.6 38 40 42 44 4.6 4fl 



Fig. 9. Curves for the number of cc. of 0.1 N HNO3, H2SO4, oxalic, and phos- 

 phoric acids required to bring 1 gm. of isoelectric gelatin to different pH (in 100 

 cc. of solution). Curves similar to those for egg albumin (Fig. 3). For the same 

 pH the ratio of HNO.3, H2SO4, oxalic, and phosphoric acids required is approxi- 

 mately as 1 : 1: 2: 3. 



