SOLUTIONS AS A FUNCTION OF TEMPERATURE 153 



the value of the ionization function likewise decreases. It is interesting 

 to examine the general course of the ionization function at different 

 temperatures. In the following table are given values of the ionization 

 function K' at a series of concentrations at 156 and 306, for potassium 

 chloride, and at 156, 218 and 306 for nitric acid. 



TABLE LV. 



VALUES OF THE IONIZATION FUNCTION K f FOR STRONG ELECTROLYTES IN 

 WATER AT HIGHER TEMPERATURES. 



Potassium Chloride. 



C X 10 3 0.5 2.0 10. 80. Temp. 



K' X 10 2 2.68 5.67 18.9 39.6 156 



0.882 13.0 306 



Nitric Acid. 



CX10 3 0.5 2.0 10. 80. Temp. 



K' X 10 2 2.68 4.87 10.7 28.0 156 



1.57 3.53 8.30 21.6 218 



0.60 1.22 2.96 8.53 306 



Allowance must, of course, be made for the more or less continuous 

 increase in the probable error of the conductance values as the tem- 

 perature rises. The uncertainty in the value of the ionization function 

 K', however, probably does not increase in the same proportion, since, 

 at a given concentration the ionization of the salt decreases with tem- 

 perature, and a given percentage error in A or A has as a consequence 

 a smaller percentage error in the value of K'. At the higher concentra- 

 tions, at any rate, the values of K' are approximately correct. In the 

 case of potassium chloride at 156, the general course of the curve is 

 similar to that of potassium chloride at 18, but the value of the function 

 is somewhat lower. At 306, the value of the function K' is markedly 

 lower than at 156. Thus, at 0.08 normal, between 156 and 306, K' 

 changes from 0.396 to 0.13. Correspondingly, at lower concentrations 

 the value of the function K' becomes much smaller. The change in the 

 value of the function K' is most marked in the case of nitric acid. For 

 this electrolyte, between 156 and 306, the value of K' decreases ap- 

 proximately in the ratio of 1 to 4. For hydrochloric acid the change in 

 the value of K' is much smaller than it is for nitric acid. Since, at 

 306, the ionization curve of hydrochloric acid differs but little from that 

 of potassium chloride, it is obvious that the value of the function K' for 

 hydrochloric acid is approximately the same as for potassium chloride 

 at that temperature. At 18 and 0.1 N, the value of K' is 0.5 for potas- 



