I MAT I BR V 



THE PRINCIPLES INVOLVED l\ THE MEAS1 REMEN1 OF THE 

 HYDROGEN l<»\ < ON( ENTRATION I 



THE METHODS OF MEASUREMENT 



The Electric Method 



In order to understand the principle of il • 

 measuring the II ion concentration, il is nee 



said < cerning the factors governing the development of electric i 



rents in chemical batteries. There may be a furtl 



knowledge in connection with th< 



which occurs during physiological activity, as in 



When a metal is immersed in a solution of 

 tendency to give off ions into the solution. 9 lar ioi 

 already presenl in this solution, and these, by t ; 

 tend to oppose the passage of the i 

 force with which the metal sends oul its ions into th< 

 tin electrolytic solution /■ h' this [ual t<» tl 



sure of the metallic ions in the solution, there will 

 generated, but it' it is greater or less than ih< 

 metallic ion, an electric currenl will beset up. When tl 

 Bure is the greater, the metal will become n< 

 ions carrj positive charges into the boIuI 



when tl smotic pressure is ir than the N..luti.>ii 



will have a positive charge, owing t<> th< 

 from the solution. 



Because of .1 called 



from the metal can uot travel an} n 

 charged mass of metal, bo that fron 

 impossible for us to lead off an : 



must form a circuit. Tin- is done n tl 7 



connecting side tubes coming fron 

 mediate vessel containing ution 



uecting the metals by wires l • 

 same metals in soluti 



rent w ill be "ate, I, 



