456 
various organic solvents such as amyl alcohol, benzene, chloroform, 
bromoform ard toluene has been investigated and it has been found 
Alcohollayer 
400 
380 
360 / 
— 
— 
— 
Erithrosine 
Pajenttlle See 
a Cima Crystal ponceau 
Ut) TTK OR 
300 400 500 mer/L 
aqueous layer 
that on increasing the concentration an proportionally smaller part 
remains in the aqueous layer'). With methylene blue, between 
aniline and water, the division coefficient is constant *). 
We have now measured for a number of dyestuffs the distribution 
between water and isobutyl alcohol (b.p. 106°). The determination 
of the colouring matter was effected colorimetrically. The temperature 
was 25°. The results are united in tables 1—19. The concentrations 
are indicated therein in mgs. per litre. 
From these tables and better still from the curves in fig. 1 it 
appears that with all these colouring matters, the division coefficient 
c ; 
“ decreases with the increase in the concentration. If the adsorption 
Cw 
In 1 ie: 
relation Ca = ae is applied we find that — varies from 0.3 (with 
n 
erythrosine A) to 1 (alkali blue and erystal ponceau). In most cases, 
however, this exponent increases with the rise of the concentration. 
This result is surprising. As the investigations of recent years have 
1) W. Herz, Der Verteilungssatz, Sanimlung chem. und chem.-techn. Vorträge 
15 (1909). 
2) Perer-Joumver, Revue gén. mat. col. 1909, 249. 
