854 
PEOFESSOE B. C. BEODIE ON THE OXIDATION AND 
rapidly boiled. The gas evolved was collected over a solution of iodide of potassium : it 
consisted of a mixture of chlorine and oxygen. The iodine formed was determined by a 
standard iodine solution in the usual manner. The hydrochloric acid was taken in very 
great excess ; the same absolute amount was used in each experiment, but diluted with 
varying quantities of water. Since a solution of peroxide of hydrogen is decomposed 
on boiling into water and oxygen, we may regard the oxygen evolved as the measure of 
the peroxide of hydrogen formed. 
Now, putting 
a=the iodine contained in 1 cub. centim. of the standard iodine solution, 
g=the quantity of peroxide of barium employed in the experiment, 
Z=the quantity of oxygen equivalent to the chlorine evolved, 
nt — ifi with its usual signification. 
then 
rj O X Ba^O^ 
I X 0-2929 
X oi[nt—t]). 
In each of the following experiments 25 cub. centims. of concentrated hydrochloric acid 
were taken. The absolute amount of pure hydrochloric acid in this concentrated acid 
was experimentally determined; it amounted to 30-33 per cent. « = 0-0029735. 
Experiment. 
Water added. 
C. 
ni—fi- 
Z. 
Mean value 
of Z. 
grm. 
I. 
0 
0-2929 
125-5 
8-015 
8-015 
; II. (1) 
5 
0-3019 
129-8 
8-047 1 
8-015 
(2) 
5 
0-3008 
127-5 
7-983 / 
III. 
6-25 
0-3006 
128-6 
7-866 
7-866 
IV. (1) 
7-5 
0-2998 
122-6 
7-654 1 
7-658 
(2) 
0-3080 
126-1 
7-662 j 
V. (]) 
10 
0-3037 
105-9 
6-528 ^ 
6-623 
(2) 
0-3044 
109-3 
6-718 J 
VI. (1) 
(2) 
15 
0-2964 
0-3025 
65-7 
64-6 
4-188 1 
3-997 J 
4-092 
VII. (\) 
20 
0-3006 
31-9 
1-986 1 
L 
1-962 
(2) 
0-2985 
30-9 
1-938 J 
VIII. (1) 
25 
0-2981 
14-8 
0-929 1 
L 
0-936 
(2) 
0-2990 
15-1 
0-943 J 
IX. (1) 
30 
0-3321 
11-6 
0-6538 
t 
0-677 
(2) 
0-3071 
11-5 
0-7005 J 
r 
X. ( 1 ) 
(2) 
35 
0-3025 
0-2954 
7-5 
7-2 
0-464 
0-4561 
0-460 
XI. (1) 
40 
0-3064 
5-7 
0-348r 
i 
0-326 
(2) 
0-3084 
5-0 
0-3035 
XII. (1) 
(2) 
60 
0-3144 
0-3008 
3-5 
3-0 
0-2083' 
0-1866 
0-1974 
XIII. 
60 
0-2973 
trace. 
Turther. Let s— the ratio of the amount of water to the amount of pure hydrochloric 
acid in the solution of hydrochloric acid employed ; and when water is saturated with 
hydrochloric acid, let s=l ; s may be termed the ratio of saturation. 
And let d= the amount of water added in each experiment to every 100 cub. centims. 
of the solution of hydrochloric acid employed. 
