LAWS OF ELECTROLYTIC DISSOCIATION 



21 



numbers of H+ and OH" ions, and at 22°C. it is lO"'' normal. 

 An acid solution contains more than 10~^ iV H+ ions and less than 

 10~^ A'' 0H~ ions, an alkaline solution represents the reverse con- 

 dition. And yet the strongest of acid solutions is not absolutely- 

 free of 0H~ ions, nor is the strongest alkaline solution entirely free 

 of H+ ions. In order to define the state of acidity, neutrality or 

 alkalinity of a fluid it is only necessary to state its [H+] or [0H~]. 

 Since the results of such measurements are usually stated in terms of 

 [H+], this time-established convention will be retained henceforth 



K 



■^ 

 St.- 



I 



- 



[M'J- 



iiO~ 



2jo' dro' 



Fia. 1 



«a7^ 



and the long term "hydrogen ion concentration" will be replaced 

 by the shorter term "Hydrogen number." Therefore, the defini- 

 tion of a 



Neutral reaction is : [H"*"] = 10"^ 

 Acid reaction is : [H+] = > 10~^ 

 Alkaline reaction is : [H+] = < 10 ~' 



The number 10~'^ above is in terms of normality or gram ions per 

 liter. 



As stated above the [0H~] is always dependent upon the [H+] 

 in the manner of the following relationship : ^ 



!i! LIBRARY 



