SALT EFFECTS OF PHOSPHATES 



171 



herent in each, and to devise means of expressing the true hydro- 

 gen ion concentration, or activity, in terms of the results given 

 by the two methods. We have therefore begun an investigation 

 of these so-called "salt effects" by the use of a number of methods, 7 

 and as phosphates are cheap and efficient chemicals for regulating 

 hydrogen ion concentrations, we are presenting here some data 

 showing that increasing concentrations of such phosphates pro- 





r 

 L 



..06 



OA 



Ln dothia oaras/T/ca 

 Bean Decoction * fa HPO+r/Jcet/'c flcid 



GrovrTh ~ 

 p/otted aqainst 

 <f Initial r» of Medium 

 o Final Ri of Medium 



Jj, ft , ft 

 * 3 



Fig. 1 



duce increasing differences between the hydrogen ion concen- 

 trations indicated by the hydrogen electrode readings and by the 

 colors of the indicators. These and other more extensive meas- 



7 Brunei and Acree: Am. Chem. J., 36, 120. Acree: Ibid, 41, 457. Loomis 

 and Acree: Ibid, 46, 5861, 632. Loomis, Meacham and Essex: J. Am. Chem. 

 Soc, 38, 2310; 39, 1133. Acree and Slagle: Am. Chem. J., 42, 130. White and 

 Acree: J. Am. Chem. Soc, 40, 1094; 41, 1212. Lubs, Cloukey and Acree: Ibid, 

 38, 2773, 2784. Mayer and Hantzsch: Ber. d. chem. Ges., 40, 3479; 41, 2568. 

 Szyszkowski: Z. Physik. Chem., 58, 420; 63, 421; 73, 269. Arrhenius: Ibid, 1, 

 110; 11, 823; 31, 197. Harned: J. Am. Chem. Soc, 38, 1916, and many other 

 excellent papers. See also many papers in Amer. Chem. J. and J. Am. Chem. 

 Soc, by Acree and coworkers on salt effects in reaction velocities. 



