DISOXIDATION EFFECTED BY THE ALKALINE PEEOXIDES. 
845 
and 
ms 
W= 
I. Peroxide of barium in excess. 
(1) n=20, Wi=10, 
s=l-015, 5 i=1-113, 
ms=ns—^=20'o — 9‘2=11‘1, 
^= 0 - 997 . 
(2) w=2, mi = 2, 
5 = 4 - 905 , 5 i= 0 - 9314 , 
7ns=«s— ^=1-846, 
a^= 0 - 99 . 
II. Hypochlorite of barium in excess. 
m=10, %=20, 
», = <( 
5 = 3 - 0126 , 5 i = 3 - 124 , ^ ( 32-4 ^ 
OTi 5 i = 30 - 155 , 
a;= 0 - 999 . 
The final result, therefore, of the decomposition is in both cases expressed by the 
equation 
Ba CIO Ba 2 02= Ba Cl + Ba 2 O + O 2 . 
1 have ascertained by similar experiments that an equivalent of chlorine in aqueous 
solution decomposes an equivalent of the peroxide of hydrogen, according to the 
equation 
Cl2 + H2 02 = 2HCl + 02. 
BecoiTiposition of Chromic Acid hy Peroxide of Hydrogen. 
The previous reactions are of a normal character. The peroxide of hydrogen and the 
permanganic acid or alkaline hypochlorite are simultaneouslydecomposed in simple atomic 
proportions, and the formation of the oxygen evolved is subject to the general law of 
atomic combination. The decomposition of the peroxide of hydrogen by chromic acid 
has a character apparently exceptional, and it is only by an attentive study of the 
reaction that it is seen to be of the same class as the preceding. 
Barreswil made the interesting observation that chromic acid in an acid solution is 
oxidized by the peroxide of hydrogen, and an evanescent blue compound formed, which 
is rapidly decomposed with the formation of sesquioxide of chromium and the evolution 
of oxygen gas. The nature of this compound is unknown. Barreswil, indeed, con- 
sidered that he had given reasons for believing it to be the chromic compound corre- 
sponding to permanganic acid. But he was unacquainted with the peculiar features of 
the reaction. 
5 z 
p= 9 - 2 . 
Two expts. 
/'7.q9q'i Mean. 
|7 92 oL 
(8-005) 
32 - 25 ) Mean. 
MDCCCLXII. 
