58 
Proceedings of the Royal Society of Edinburgh. [Sess. 
1 - — 
232 
Also the con- 
495 /jl/ul. I left the constitution of the red phase undetermined, and assumed 
that it was represented by the formula CoC1 2 .ccH 2 0. 
Let the concentrations of cobalt chloride and water in grm.-mols. per 
litre be c x and c 2 respectively. Then the concentration of the blue phase 
in any solution is anc ^ ^he re d phase l 
centration of the uncombined water is c 2 — ^ 
The equation of the reaction is 
CoCl 2 + #H 2 0 = CoCl 2 . xH 2 0. 
Hence by the law of mass action 
A \-q 
1 
A \ 
32 ) C ^ 
A \ 
m) c ' x - 
(232 c 0 { c > 0 232) Ci *} ( ! 232)“' 
k; 
i.e. c 9 
232 ) CiX ( 
1 
232 - A\ x 
A k ) 
Take two solutions and let their values of A, c v c 2 be A', c\, c' 2 , and A", 
c" 2 respectively. By combining the equations for each solution we get 
1 
A" 
/, A' \ , f (232 -A') A" | * ( „ 
V 1 232/ 1 ( A'(232 - A") J | fc - 
232 
} 
If A' and A" are approximately equal, and x has a fairly high value, 
the x th root becomes very nearly equal to unity, and the last equation 
becomes 
0 O — Co 
X = 
1 - 
A"\ t 
c , 
232/ 1 232, 
The condition was laid down that the quantity under the root should lie 
between ’8 and 1*2. Only three pairs of solutions showing the red absorp- 
tion band were found to satisfy this condition, and in these cases x was 
calculated. Data for these solutions are tabulated below, the values of c 2 
being corrected so as to include the water originally in the alcohol : — 
Solution. 
c x . 
c 2 . 
A. 
I c 
•8738 
9-856 
70 
lla 
•38 
3-605 
78 
Id 
•8224 
12-70 
12 
III a 
•10 
3 74 
11-2 
le 
•771 
15-66 
3-92 
lie 
•34 
9-86 
36 
x. 
| 17-4 
J 13-0 
| 137 
Mean value of cc = 14*7. 
