136 Table 117. 



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, 

 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. 

 dx 



k depends on the temperature and the concentration, c gives the gram-molecules per litre. 

 The unit of time is a day. 



Compiled from Landolt-Bornstein-MeyerhofEer's Physikalisch-cbemische Tabellen. 

 Smithsonian Tables. 



