56 



CONDUCTIVITY AND VISCOSITY IN MIXED SOLVENTS. 



In table 32 the values are about the same as for ammonium bromide. The 

 data for the mixture and for methyl alcohol were furnished by Zelinsky and 

 Krapiwin and by Carrara, respectively. 



From results given by Jones and Lindsay it is possible to calculate the dis- 

 sociation of lithium nitrate in the 50 per cent mixture at two temperatures, 

 and 25, assuming that here, as in the other cases, complete dissociation is 

 reached at v = 1024. It is known that in aqueous solution complete disso- 

 ciation is not reached as soon in the case of lithium salts as with potassium 

 or sodium salts. Less value must therefore be attached to the results given 

 in table 32. 



Values of the dissociation for hydrochloric acid in the 90 per cent and in 

 the 69.75 per cent mixtures at and at 25 are also given in table 33. It will 

 be remembered that the results in the latter mixture were irregular. No 

 stress can, therefore, be laid upon these figures. We have taken the deter- 

 minations for v = 92.4 as the limiting values in this case. 



TABLE 33. Dissociation of hydrochloric acid in 69.75 per cent and 90 per cent methyl 



alcohol, in water, and in methyl alcohol. 



The values for conductivities in water are taken from Ostwald; 1 those for 

 methyl alcohol from Carrara. 



It is observed in table 33 that the dissociation is greater in the 69.75 per 

 cent mixture than in water at the corresponding dilution. This, however, is 

 not the case for the 90 per cent mixture. It is also interesting to note that 

 the dissociation is apparently greater at than it is at 25, and this is true 

 for the 90 per cent mixture, where the results are more reliable than those 

 for the 69.75 per cent mixture. 



We have suggested that the dissociation in the 50 per cent mixture may be 

 due in part to the presence of the hydrate CH 3 OH . 3 H 2 O. This compound 

 would be more stable at a lower than at a higher temperature, and would be 

 present to a greater extent at the lower temperature, and therefore the dis- 

 sociation might be greater. This result should be shown by salts as well as 



1 Journ. prakt. Chem., 140, 300 (1885). 



