467 
Chemistry. — “On the Quaternary system: KCl—-CuCl,—BaCl,— 
H,O.” By Prof. F. A. H. Scretnemakers and Miss W.C. pr Baar. 
(Communicated in the meeting of September 28, 1912). 
In the previous articles *) we already discussed the equilibria 
occurring at 30° in the quaternary systems : 
NaCl — CuCl, — BaCl, — H,0 
and NH,Cl — CuCl, — BaCl, — H,O 
In the first system no double salt is formed, in the second 
occurs the double salt CuCl, .2NH,Cl.2H,O0. As in the system : 
KCl — CuCl, — BaCl, — H,O 
two double salts may appear, we have now investigated this system 
also. 
The two double salts are: 
D,22 = CuCl, .2 KCl. 2 H,O 
and Di1 == CuCl, sG: 
The equilibria occurring have been investigated at 40° and 60°; 
these temperatures have been chosen purposely because at the first 
temperature (40°) only one of the double salts (Dj22) still occurs; 
at the other temperature (60°) both double salts appear. 
In the ternary system KCl— BaCl, —H,O occur as solid sub- 
stances, at 40° and 60° KCl and BaCl, . 2 H,O so that the isotherms 
also consist of two saturation lines. 
The monovariant (P) equilibria occurring in the ternary system 
KCl — CuCl, — H,O have been described previously by W. Mrynr- 
HOFFER”); the isotherm of 30° has been determined by H. Frrrppo *). 
From these investigations it follows that below 57°, in addition 
to KCl and CuCl,.2H,O also occurs the double salt D122, between 
57° and 92° the double salts D,j22 and D,, and above 92° only the 
double salt Die 
The isotherm of 40° therefore consists of the saturation lines of: 
KCl , CuCl,.2H,O and Dj22, that of 60° of the saturation lines of 
KCl E CuCl,.2H,0, Dj 22 and Din. 
The equilibria appearing in the quaternary system may be repre- 
sented in space, in the well known manner with the aid ofa tetra- 
hedron, whose four apexes indicate the four components: KCI, CuCl,, 
BaCl, and water. In Figs. 1 and 2 is found a projection of the 
1) F. A. H. Scuremvemakers and Miss W. C. pe Baar. Chem. Weekbl. 1908. 
2) W. Meyernorrer. Z. f. Phys. Chem. 3 336 (1889). 
’ . yo» » 5 97 (1890). 
3) H. Fiero. Not yet published. 
