148 HYDRATES IN AQUEOUS SOLUTION. 



chloride in ethyl alcohol, as worked out by Jones and Getman.* Since in 

 the preparation of the solutions both solvent and dissolved substance were 

 taken in weighed quantities, the question of the change in the specific gravity 

 of the solutions does not come into play. 



Jones and Getmanf interpreted these results by the boiling-point method, 

 in ethyl alcohol as the solvent, in the same manner that they had previously 

 interpreted their results obtained by the freezing-point method in aqueous 

 solutions. The abnormally great rise in the boiling-point of ethyl alcohol 

 produced by certain salts, is due to combination between the dissolved sub- 

 stance and part of the solvent to the formation of alcoholates in solution. 

 The part of the alcohol that was in combination with the dissolved substance 

 would thus be removed from the field of action as far as solvent is concerned. 

 There being less alcohol present acting as solvent, the rise in the boiling- 

 point produced by the dissolved substance would be, of course, greater than 

 if all the alcohol was playing the role of solvent. 



This suggestion accounts for the facts in the case of solutions in alcohol, 

 just as the hydrate theory had explained the abnormally great lowering of 

 the freezing-point of water produced by a large number of salts, especially 

 when the concentrations were great. 



The object of this part of the investigation is to extend the earlier work 

 of Jones and Getman to a larger number of salts, and to more than one 

 non-aqueous solvent. Jones and McMaster repeated the work with a few 

 of the same substances in ethyl alcohol that were employed by Jones and 

 Getman, and have added a number of substances to the list of those that 

 were earlier studied. They worked with lithium chloride, lithium bromide, 

 and lithium nitrate in methyl alcohol; and with lithium chloride, lithium 

 bromide, lithium nitrate, and calcium nitrate in ethyl alcohol. 



In making the boiling-point measurements, the boiling-point apparatus 

 of JonesJ was employed. In order to be independent of correction for 

 changes in the barometer, two pieces of boiling-point apparatus were used. 

 In one of these the pure solvent was boiled, and in the other the solution. 



The alcohols used in this work were dehydrated by the usual methods, 

 and precaution taken to keep them free from moisture when transferred 

 to the boiling-point apparatus. The conductivity of the methyl alcohol, 

 at 25, was 2 x 10~ 6 , and that of the ethyl alcohol, from 1 to 2 x ICH. The 

 salts were all completely freed from water. The usual precautions were 

 taken in making the boiling-point measurements, and the proper correction 

 applied for the solvent that existed in the apparatus in the form of vapor. 

 The top of the condenser was closed by means of a tube filled with calcium 



*Amer. Chem. Journ., 32, 339(1904). flbid., 32, 342 (1904). llbid., 19, 581 (1897). 



