SCHLUNDT — DIELECTRIC CONSTANTS OP PURE SOLVENTS. 



379 



however, has a very low dielectric constant, the value being in- 

 termediate between the values of chlorine and bromine. The 

 dielectric constant of liquid chlorine was determined by Linde, 1 

 who found the value 1.93 at 14° C, and by Coolidge 2 , who ob- 

 tained the value 1.87 at 14.3° The values obtained for liquid 

 cyanogen (Table V)and bromine are 2.52 and 3.18, respec- 

 tively, at 23° C. 



For the purpose of this discussion, the inorganic solvents 

 whose dielectric constants were measured, are divided into two 

 groups. One group contains the solvents whose dielectric con- 

 stants range from three to five, while the other group contains 

 the solvents whose dielectric constants range from nine to thirty- 

 three. 



The ionizing power of these solvents has been investigated by 

 Kahlenberg and Lincoln 3 , and more fully by Walden. 4 The 

 electrical conductivity measurements of Walden show that the 

 solvents with low dielectric constants yield solutions with tetra- 

 ethylammonium iodide, which do not conduct well enough to 

 make quantitative measurements profitable, while the other sol- 

 vents with relatively higher dielectric constants yield solutions 

 with the same salt and with other salts that conduct fairly well. 

 (See Table II.) Here then we have a good illustration of the 

 Nernst-Thomson rule, that the greater the dielectric constant of 

 a solvent the greater is its dissociating power. The following 



i Wied. Ann. 56, 546, (1895). 



8 Wied. Ann. 69, 123, (1899). 



» Jour. phys. Chem. 3, 12, (1899). 



* Berichte d. Deutsch. Chem. Gesel. 32, 2862, (1899). Zeit. anorg. Chem. 25, 209, (1900). 



