New York AGRICULTURAL EXPERIMENT STATION. 255 
Taste XVII.— SHowinc Errect or CoNCENTRATION OF SuLtpHuRIC ACcID 
con. He SOs in casein 
Upon VALUE OF EourLisriuM Rat10o—————-—__—— 
2 con. He SOs in water. 



Ca eye ee Sb yates t=) Goq 
o 808s oe} o3o°" Pipa: 
sO paw o om ey 8-20 
8 oD, ga eeu o95 
asacs| sed | Bata.) 8 
No. DESCRIPTION. S° 8e5| 58:3 he heist aged feat FL RO, 
Sg d0.08 Sus Fudu'd ot ge 
Og fess O'g a O35 ioe =—oO6 8 
aacead, sas Facdo | Bae 
fe) fs) fe) 
oO oO oO ie 
1 | Acid as used in experiment......... 4.090 4.08 0 0 
2 | Acid after shaking 100 c.c. with .4795 
Bee CASEI gv. oy. «. gov shea hie’ se ts 1.547 1.60 509.4 329.4 
3 | Solution obtained by replacing 50 c.c. 
of No. 2 with water and shaking 
until equilibrium was restored.... 1.083 1.10 445.0 411.0 
4 | Solution obtained by replacing 50 c.c. 
of No. 3 with water and skaking 
until equilibrium was restored.... 0.828 0.82 385.4 465.5 
5 | Solution obtained by replacing 50 c.c. 
of No. 4 with water and shaking ‘ 
until equilibrium was restored.... 0.667 0.64 302.7 498.7 


It is evident that the value of the ratio varies inversely as 
the concentration of the acid; it increases with the dilution. 
This increase is similar to that observed in most cases of adsorp- 
tion phenomena and, moreover, occurs in accordance with the 
D 
C, 
large proportion of adsorptions, that are reported,’ in which 
B = a constant; C, = amount of solute adsorbed per unit mass 
of adsorbent (= concentration of sulphuric acid in casein) ; 
C, = concentration of solute in solution in contact with adsor- 
bent (= concentration of sulphuric acid in water); p, the ex- 
ponent of c, is a constant, dependent like 8 upon the substances 
and conditions; p — 1.95 in the present case. In the following 
table are arranged all the equilibrium results recorded in the 
foregoing tables. They show the regular increase of the ratio with 
the dilution of sulphuric acid and the approximate constancy of £, 
independant of the manner in which equilibrium was obtained. 

exponential formula, B= , found empirically to hold in a 
1Schmidt. Ztschr. Phys. Chem., 15:56. 1804; Walker and Appleyard. 
Jour. Chem. Soc. 69:1334. 1896; Freundlich. Zischr. Phys. Chem., 57:385. 
1900. 
