ORGANIC SOLVENTS. 11 



In connection with their work in acetone they make the following remark- 

 able statement: 



We have found by the boiling-point method that the following salts in acetone have 

 normal molecular weights : Cadmium iodide, lithium chloride, sodium iodide, mercuric 

 chloride, and ammonium sulphocyanate. 



And that these substances in acetone conduct the current. Results l 

 obtained in the physical-chemical laboratory of the Johns Hopkins University 

 indicate that this statement is erroneous. 



ACIDS. 



The dissociating power of formic acid has been quite elaborately investi- 

 gated by Zanninovich-Tessarin. 2 In his work he used mainly the freezing- 

 point method, but also studied the conductivity of a few salts in this solvent. 

 He measured the freezing-point lowering of formic acid produced by the 

 following substances, at dilutions varying from 0.34 to 3.4 normal (and in 

 some cases at even greater concentration) : Potassium, sodium, ammonium, 

 and lithium chlorides; potassium, sodium, and ammonium bromides; hydro- 

 chloric, acetic, and trichloracetic acids. Formic acid is one of the strongest 

 dissociating solvents next to hydrocyanic acid and water. The behavior 

 of hydrochloric acid in this solvent is very remarkable. Not only does it 

 show no dissociation, but the molecules are actually polymerized. Although, 

 as just mentioned, the freezing-point lowering showed no dissociation, the 

 conductivity in this solvent was very considerable. This may be due to the 

 fact that while a majority of the molecules were polymerized, some were disso- 

 ciated into ions which conducted the current. The conductivities of potassium 

 and sodium chlorides in this solvent were also found to be very large. 



Zanninovich-Tessarin 3 has also determined the freezing-point lowering pro- 

 duced by sodium bromide and lithium chloride in acetic acid. The former 

 gave normal values, indicating no dissociation; while the latter showed marked 

 polymerization. 



The conductivity of sulphuric acid in acetic acid has been measured by 

 Jones, 4 who found that the molecular conductivity, which was small at all 

 dilutions, increased with the dilution to a certain point, and then decreased with 

 further increase in the dilution of the solution. This is somewhat analogous 

 to the result obtained by Kablukoff 5 for hydrochloric acid in ether and in 



isoamyl alcohol. 



THE NITRILES AND CYANOGEN. 



Dutoit and Aston 8 determined the conductivities of mercuric chloride, 

 sodium bromide, cadmium bromide and iodide, ammonium sulphocyanate, 

 and silver nitrate, in propionitrile. The investigation was extended by 



1 Amer. Chem. Journ., 27, 16 (1902). * Amer. Chem. Journ., 16, 13 (1894). 



2 Ztschr. phys. Chem., 19, 251 (1896). 6 Loc. cit. 



3 Ibid., 19, 255 (1896). Compt. rend., 125, 240 (1897). 



