138 TABLE 124. 



DIFFUSION OF AN AQUEOUS SOLUTION INTO PURE WATER. 



If k is the coefficient of diffusion, dS the amount of the substance which passes in the time dt t 

 at the place x, through q sq. cm. of a diffusion cylinder under the influence of a drop of concen- 

 tration dc I ' dx, then 



dS = -kq $ dt. 

 ax 



k depends on the temperature and the concentration. 

 The unit of time is a day. 



c gives the gram-molecules per liter. 



Compiled from Landolt-Bornstein-Meyerhoffer's Physikalisch-chemische Tabellen. 

 SMITHSONIAN TABLES. 



