338 



EEPOET — 1886. 



The next little table contains the estimated limiting values of molecular con- 

 ductivity for infinite dilution. First for fairly neutral substances, next for acid 

 and allialine bodies. The ionic velocitiescorresponding to these numbers are, for 

 the first set, between '0014 and •0010, and for the second set between -0040 and 

 •0013 centimetre per second, rate of travel of anions past cations, when urged by 

 a slope of potential of 1 volt per centimetre. 



Limiting Values of Specijic Molecular Conductivity for extreme dilution. 

 (A). Oedinary Salts. 



10-' 



' These values are all of the same order of magnitude, but they are by no means 

 equal to one another.' 



(B). NOX-NEUTBAL BODIES. 



10-' 



L.\.w OF Specific Ionic Velocity. 



Taking into account the results of Hittorf on migration, Kohlrausch estimates 

 as the relative velocities for the following ions in a solution of strength defined by 

 m = "1 : — 



K Am Na Li Ag H ^Ba ^Mg ^Zn 



52 50 32 24 42 272 "30 '26 24 



01 

 54 



I 



55 



NO3 



48 



CIO3 

 42 



C.JIjO,, 

 '26 



OH 

 143 



and with these numbers he proceeds to calculate the conductivity of solutions of 

 this strength (?)i = -l) of the various substances, and to compare them with experi- 

 ment.' The agreement between observed and calculated numbers for a large num- 

 ber of substances as regards both conductivity and migration is remarkable. 



For instance, here are some calculated numbers to be compared with the 

 column headed '1 of the table just quoted, page 337. 



But several substances remain intractable. For instance, acetic acid gives, 

 calculated, 2980 ; observed, 43. 



' See table on page 215 of Kohlrausch's memoir. 



I 



