of Gibbs's Theory of Surface- Concentration. 473 



The values o£ the concentration are plotted against tension 

 Fig. % 



in fig. 2. 



52 



Oh 

 oO 



OQ 



a 



a- 49 



53 43 



\ r 



0*01 0'02 0-03 



Molar Concentration. — Silver Nitrate. 

 The calculated adsorption, namely 



c da 



St Jc* 



has the following value for a concentration - 1 ,, molar : — 

 c = O'OO.'U grm. per c.c. 



R = 



(S-4 x 10 7 orgs 



molecular weight 

 The molecular weight at this dilution has been found by 

 Smits * to be 94. x = 289° abs. 



da ■ 



dc 



is tlie tangent to the curve at -V molar concentration and 



is equal to 



1*9 dyne/cm. 



Hence 



0-0034 grm./c.( 



556. 



c da 

 JiTdc 



= 7*3 x 10~° gram per cm. 2 



This refers to the salt AgN0 3 , so that on the assumption 

 * Smits, Zeitschr. Phys. Chem. vol. xxxix. p. 418 (1902). 



