ELECTROLYTIC SOLUTIONS IN VARIOUS SOLVENTS 51 



These intermediate curves apparently form a continuous series be- 

 tween the two extreme types and, by suitably changing the condition of 

 the solutions, a continuous shift takes place in the curve from one ex- 

 treme toward the other. For example, as the temperature of a solution 

 is increased, there is a shift from the aqueous type toward the type 

 exemplified by the solutions in hydrogen bromide. This is clearly the 

 case with solutions in sulphur dioxide. As we have already seen, at 

 33 the conductance of solutions in sulphur dioxide increases continu- 

 ously with decreasing concentration, although there is a certain concen- 

 tration interval over which the conductance change is extremely small. 

 At a temperature of 10 this curve exhibits a maximum and a mini- 

 mum, similar to that just described in the case of solutions in methyl- 

 amine. At still higher temperatures, the maximum and minimum be- 

 come more pronounced. 



Methylamine may be looked upon as a derivative of ammonia and 

 the relation between methylamine and ammonia solutions may be ex- 

 pected to be similar to that between the alcohols and water. As we 

 shall see presently, ammonia solutions, for the most part, belong to the 

 aqueous type; that is, the conductance increases throughout with de- 

 creasing concentration. In the case of methylamine solutions, as we 

 have seen, the curve exhibits a pronounced maximum and minimum. 

 Solutions in ethylamine are still further removed toward the bromine 

 type, as is apparent from the values given for the conductance of silver 

 nitrate in ethylamine in Table XVII: T 



TABLE XVII. 

 CONDUCTANCE OF AgN0 3 IN C 2 H 5 NH 2 AT 33. 



V 0.9928 1.981 3.953 15.73 62.65 125.0 



A 5.67 5.820 4.320 1.677 1.038 1.041 



In this case the conductance decreases with decreasing concentration, but 

 it is evident that at the lower concentrations the conductance does not 

 approach the value zero as a limit. In fact, it is apparent that, at dilu- 

 tions slightly greater than 125 liters per mol, the conductance curve will 

 again rise. Indeed, solutions of certain other salts in ethylamine exhibit 

 a distinct minimum in the neighborhood of 0.01 normal. The conductance 

 curve of solutions in amylamine resembles that of solutions in bromine 

 very closely, the conductance decreasing throughout with decreasing con- 

 centration and apparently approaching a value of zero so far as has 

 been observed. 



T Fitzgerald, Joe. ctt. 



