Ionizing Power of Solvents. 



Trichloracetic Acid and Water. — Pure trichloracetic acid melts 

 at about 52°. The measurements were made at 60°. 



Per cent, of water 



Cell. 



Resistance 



Conductivity at 60° 



by weight. 



at 60°. 



in C.G-.S. units. 







2 



>1 million. 



-15 



0-80 





280000 



0-5x10 



1-59 





70000 



2-0 „ 



313 





8700 



162 „ 



4-62 





2040 



68-9 „ 



606 



M 



665 



211-5 „ 



7-47 





277 



507-6 „ 



1015 





76-8 



1830 



13-90 





22-8 



6167 



1948 



1 



109 



21150 



28-74 





33-5 



68800 



530 





9-7 



238000 



68-8 





7-5 



307000 



805 



" 



79 



292000 



91-8 







185000 



959 







105000 



9795 







57100 



98 98 







29900 



The numbers below the dotted line are calculated from Ostwald's 

 results for solutions of trichloracetic acid in water. 



Formic Acid and Water. — The formic acid sold as pure 

 had a freezing-point of 4- l O- 60. On adding 0'5 c.c. of 

 water to 25'99 grams of acid it froze at — l°'l, a lowering of 

 2°*7, and a further addition of 0*5 c.c, making 1 c.c. in all, 

 gave a mixture freezing at — 3°*8. Thus the lowering pro- 

 duced by the second half-gram of water was also 2°'7, and 

 the depression of the freezing-point is proportional to the 

 quantity of water present. The freezing-point of the 

 anhydrous acid is taken by Raoult to be 8*5, so that the acid 

 used in these experiments contained about 2'47 per cent, of 

 water to begin with. Allowing for this, and correcting the 

 conductivity results for the calculated conductivity of the 

 pure acid, we get : — 



