DISOXIDATION EFFECTED BY THE ALKALINE PEEOXIDES. 
849 
From these data we obtain the following values for r, and x : — 
y- 
Mean value Mean value 
of y. of X. 
r. 
y- 
X. 
23. 
3-720 
2-72 
1-696 
24. 
3-648 
2-648 
1-728 
25. 
3-705 
2-705 
1-703 
26. 
4-888 
3-888 
1-803 
27. 
4 864 
3-864 
1-799 
28. 
1-833 
29. 
6-08 
5-08 
1-911 
30. 
6-16 
5-16 
1-905 
31. 
6-20 
5-20 
1-909 
32. 
7-39 
6-39 
2-034 
33. 
1-977 
34. 
8-554 
7-554 
2-023 
35. 
8-743 
7-74 
1-989 
36. 
1-962 
37. 
9-993 
8-993 
2-003 
38. 
2-003 
39. 
11-24 
10-24 
2-032 
40. 
O.QOO 
41. 
21-816 
20-816 
2-079 
42. 
2-043 
[Mean value 
I of y. 
Mean value 
of X. 
1 . 
2 . 
3. 
4. 
5. 
6 . 
7. 
8 . 
9. 
10 . 
11 . 
12 . 
13. 
14 . 
15. 
16 . 
17. 
18. 
19. 
20 . 
21 . 
22 . 
0-068 - 
0-110 
0-123 
0-164 
0-247 
0-329 
0-402 
0-814 — 
I’lOO 
1- 223 
1-222 
2- 444 
2-446 
2-480 
12-65 0-959 1 
0-991 J 
9-02 1-103 I 
1-123 / 
7-34 1-042 1 
1-026 J 
5-25 1-037 
i 1-037 
3-16 I 1-031 
j 1-043 
2-11 1-033 1 
I 1-037 J 
1-61 1-017 1 
1-011 / 
0-25 1-093 I 
i 1-111 / 
0-10 1-001 
0-223 1-223 \ 
0- 222 1-222 j 
1- 444 1-506 
1-446 : 1-462 
1-480 , 1-507 
12-65 
9-02 
7-34 
5-25 
3-16 
2-11 
1-61 
0- 25 
0-10 
0-222 
1- 457 
0- 975 
1- 113 
1-038 
1-037 
1-037 
1-035 
1-014 
1-103 
1-001 
1-222 
1-492 
2- 691 
3- 876 
5- 15 
6- 39 
7- 647 
8- 993 
10-24 
20-816 
1-709 
1-811 
1- 9I8 
2 - 000 
1- 992 
2- 003 
2-027 
2-061 
A graphic delineation of the results is given in the curve annexed, Plate XXXVII. 
It will be observed, on inspection of this line, that, so long as the chromic acid is not 
in defect, the two substances lose equal amounts of oxygen, according to the equation 
2 Cr^ O3+ 3 H, Ciq O3+ 3 0+ 3 ; 
that when the amount of oxygen in the peroxide of hydrogen is greater than that con- 
tained in the chromic acid, more of the peroxide of hydrogen is decomposed, but never 
the whole amount taken, and that the amount decomposed increases with the propor- 
tion taken until the peroxide of hydrogen contains as much as eight and a half times the 
amount of oxygen cont-ained in the chromic acid ; that after this point the decomposition 
becomes constant, the peroxide of hydrogen losing twice the amount of oxygen lost by 
the chromic acid ; and that no further increase in the proportion of the peroxide of hydro- 
gen taken causes this limit to be exceeded, the final result of the change being expressed 
by the equation 
2Cr2 O3-I-6H2 02=014 O3-I-6H2 O-J-90. 
In what light are we to regard the decomposition between these extreme limits I Are 
we to consider that the two substances are capable of reacting in any proportion, and 
that the simple atomic decomposition is the limit of an indefinite action varying accord- 
ing to the mass I or are we not rather to believe that this apparently indefinite action 
is the sum of certain normal chemical changes which take place in simple atomic ratios, 
but which vary in absolute amount I 
The following experiments indicate that the latter hypothesis is correct, and that the 
reaction between the extreme limits is not homogeneous, but consists of two chemical 
