8 On the Ionizing Poiver of Solvents. 



Fig. 5. — Water and Formic Acid. 



O 40 



c0 -40 50 tiu 70 80 90 



Percentage of Water. 



The curve for water in formic acid, however, does not 

 resemble these. It is, till the proportion of water reaches 

 about 40 per cent., a straight line. This has been confirmed 

 by Dr. Novak's much more elaborate experiments. We have 

 here, then, a form of curve which approaches that of a 

 typical electrolytic solution, though it does not quite coincide 

 with it. Now formic acid, as we have seen, has a dielectric 

 constant of 62, a number which approaches that of water, 75. 

 Could we find some liquid whose constant was greater than 

 75, it seems probable that it would form a solvent in which 

 water would be an electrolyte, just as common mineral salts 

 and acids are electrolytes when dissolved in water. 



The forms of the curves indicate that the solutions of water 

 in these three acids are not of the same nature as those of 



