( 522 ) 



which he carried out his fractional crystallisations, it is possible that 

 this was not the same ;is in Vokrman's experiment and this might 

 account for the difference. 



Dr. Voerman has finally been engaged in the determination of the 

 conductivity power of the two acids and their mixtures in the hope 

 of obtaining indications of a combination of the two acids when in 

 solution. The observations are as follows : 



CONDUCTIVITY POWER OF «-THIOPHENIC ACID AT 25°. 



Average 0.031G 



In this table, v represents the volume in which 1 mol. is dissolved, 

 H the molecular conductivity power, a the degree of dissociation, 

 100 k the dissociation constant according to Ostwald X 100. 



The conductivity power has been determined, previously, by 

 Ostwald (Ph. Ch. 3, 384) who found for 100 £ 0,0302, and by 

 Bader, (Ph. Ch. 6, 313) who found for 100 k 0,0329. 



CONDUCTIVITY POWER OF /?-THIOPHENIC ACID AT 25°. 



100 k 



Avpragft 0.00783 



