54Q  Preservation  of  Hydrogen  Peroxide.   {Aj£'ce^iJer  ^i™' 
Series  I. — Effect  of  Several  Acids  and  Salts. 
The  experiments  of  series  I  and  II  were  preliminary  and  were 
designed  to  give  a  general  idea  of  what  behavior  might  be  expected 
so  that  the  final  experiments  might  be  better  planned.  The  substances 
in  series  I  were  added  approximately  in  the  proportion  of  1.5  gms. 
to  the  litre  of  peroxide  solution.  One  c.c.  of  the  original  solution 
required  14.75  c-c-  tenth-normal  thiosulphate. 
Total  time  of  standing. 
4  days. 
12  days. 
29  days. 
S3  days 
H2SO4  
. .14.65. 
. . . .14-35- • • 
•13 
55-  • 
. .12.45 
H3PO4  
. . I4.6  . 
• • • -I4-35- • • 
•13 
80.  . . 
..12.85 
HC1..  
..14.6  . 
....14.40... 
•13 
90.  . 
- -13-05 
Succinic  Acid  
. .14.45. 
• • • -I3-95- • • 
•13 
25-- 
• .12.45 
KC1  
• .14-25- 
....12.75... 
.  8 
75- 
NaCl  
. .14.25. 
. . . . 12 .40. . . 
.  2 
15 
K2S04  
• -13-75- 
. . . .  9. 10. . . 
.  2 
80 
(NH4)2S04  
13-15- 
. ...  8.30... 
.  2 
90 
Mg  so4  
•I3-35- 
. ...  8.80... 
.  2 
50 
BaCI2  
..14.10. 
 12.25. . . 
•  5 
75 
Acetanilide  
..14.  7- 
....14.65... 
.14 
55- • 
• -14-45 
Original  Solution  
. .13.65. 
. . . .11.45- • • 
•  5.65.. 
..  1.65 
Series  II. 
.14-30 
One  c.c.  of  the  original  solution  required  13.80  c.c.  tenth-normal 
thiosulphate. 
Total  time  of  standing  n  days         23  days         135  days 
Original  solution  10. 75   6.25 
1 
Acetanilide 
2000 
HC1 
 13-75  13-70  13-45 
 13-45  13  00   9.20 
 13  30  12.85   0.15 
 13  00  12.15   6.55 
 13-30. . .  .,12.80   8.65 
H3P04^-  J3-30  12.85   8.45 
2000 
HC1—  +  NH4C1-^-  J3-40  12.80   8.45 
2000  2000 
HC1 
2000 
HC1  —  +  NaCl  —  
2000  2000 
HC1  —  +  Na2Si03  (anhydrous)  — - 
2000  2000 
H3P04  — —  +  Na2HP04  (anhydrous)   
2000  2000 
1 
6000 
12.95  11.90   5.20 
