1135 

 TABLE 2. 



mean 0.0327 



be expressed in the same units as the concentration of the urea, 

 in grams per 100 c.c. As pff= 7.52 means a hjdrogen-ion concen- 

 tration of 10~8 X 3,02 in the usual units, grammolecules per Litre, 

 we have here lO-» X 0,302 g. H. in 100 c.c. 



From this ?i = 0,047 X 10'. 



In order to show, that in these estimations a high accuracy is 



wanted, but is hardly to be expected in the result, and that the 



deviations are within the limits of experimental errors, we may, 



nc 

 for instance, calculate , assuming that for ^=20 the titration 



0,434 ^ 



had given 8.05 instead of 8.1. 



From 



1 / nc \ 1 



0,5768 4- 0,00735 | 



20 V0,434 

 would then follow 



J 90 V0,434 



nc 



0,1128 + 0,00229 



) 



nc 



0,434 



= 0,0426. 



Considering, that the two small samples of Sqja-meal, weighed 



Jan. 31st 1917. 



TABLE 3. 



(Fig. 2 B) 



