240 



ELECTROCHEMISTRY 



Continuing the addition of acid (HCl) to the above solution 

 of ovomucoid a remarkable phenomenon is observed, namely, 

 that doubling the amount of acid in the solution does not appreciably 

 alter its freezing-point * and, consequently does not alter the total 

 number of ions per cubic centimeter of the solution. Evidently, 

 upon further addition of acid, the remaining nitrogen atom of the 

 diamino radical becomes neutralized and the ion 



H CI 



\ 

 H CI 



R 



is formed. 



The form of the dilution-law which we should apply to these 

 solutions is therefore (Cf. equation (v)) : 



1.037 X 10-2 1 115 X ia-6 



m = ; ; ^ — X + 



X^. 



p{u-\-v) pK{u + vy 



Applying this equation to the results enumerated in Table 

 m = 5.63 a; + 117,000x3. 



XIX we obtain 



In the accompanying table the experimental and calculated values 

 of m are compared. In the third column is given the degree of 

 dissociation of the salt, estimated as the ratio of the calculated 

 value of 5.63 x to the calculated value of m. 



TABLE XXVII. OVOMUCOID CHLORIDE 

 /" (45X10~* equivalents HCl per gram) 



The same equation applies so nearly to the experimental results 

 obtained with ovomucoid sulphate (Table XX) that it is not 

 necessary to recompute the constants for this salt. 



* The freezing-point-depression due to free ovomucoid is only one-third of 

 that of the above solution, namely, 0.03 ± 0.005 degree for a 4 per cent 

 solution. 



