404 
and the degree of dissociation « (no doubt influenced by it) of the 
molten alcali-halogenides on one side, and the P, As and Sé-halo- 
genides on the other side. 
In the ease of the Bi-salts, which approach already much more 
closely to the real metallic salts, the influence of the combined 
halogen manifests itself immediately in another way: the y-t-curve 
for BiBr,, although for a greater part coinciding with that of 57C7Z,, 
is situated just beneath the latter. Previously we found in the case 
of organic liquids, being also compounds, which do not show an 
electrolytical dissociation, that the presence of electronegative atom- 
groups or elements tends generally to increase the values of 7. The 
specific influence of the substitution of three chlorine-atoms by three 
bromine-atoms, or of As by Sh, ete. in the case of these also only 
slightly associated liquids, perhaps could be thought comparable with 
the mentioned peculiarity. 
For the u-f-curves the same regularities as for y-/-curves, are present 
in this case: contrary to what was found in the series of the alcali- 
salts also here the g-/-curves are situated regularly above or beneath 
each other, all in connection with the atomic weight of the combined 
elements. The curve for BiC/, is here certainly situated completely 
beneath that for BiBr>, while those for Asbr, and ShCT, are almost 
coinciding. (fig.) 2). 
Thus contrary to these of the alcali-halogenides, the «-t-curves 
Specific Surface-Energy 
ug in Erg per cm?. 
1450 
7350 
1250 
7150 
7050 
950 
850 
750 
650 
550 
450 
ae Temperature 
307-10" 10° 30° 50° 70° 90° 710° 130° 150°110° 190° HO°LI1) LSG ZM 2900" 530 ISD" 570" AIN" 490 450 
Fig. 2. 
are here situated in the same arrangement as the y-/-curves; an 
irregularity like that found in the first case, is not observed here, 
which evidently is connected with ‘the fact, that no appreciable 
electrolytic dissociation plays a rôle here. 
Laboratory for Inorganie and Physical Chemistry of the University. 
Groningen, Holland, June 1916. 
