BLEACHING COMPOUNDS OF CHLORINE. 
303 
But those who admit that the chlorides of oxides are mix- 
tures of metallic chlorides and hypochlorites, should believe 
with Balard,* that hypochlorous acid is capable of decompos- 
ing the chlorides of the alkaline earths, with formation of a 
mixture of chloride and hypochlorite. Now, it is difficult to 
suppose that this acid is able to convert such fixed compounds 
as these chlorides into others so unstable as the hypochlorites. 
Besides, Balardt has observed that hypochlorous acid does not 
combine with peroxide of iron, while Grouvelle has announced 
a soluble, bleaching chloride of peroxide of iron, which has 
obliged Balard to consider this bleaching chloride as a mix- 
ture of hypochlorous acid and perchloride of iron, and he thus 
explains why it produces hypochlorous acid when distilled. 
But the chloride of potassa, with excess of chlorine, submitted 
to distillation, also gives hypochlorous acid and a metallic 
chloride, which should induce us <o believe the two chlorides 
analogous in composition. I am even inclined to think that 
the formation of hypochlorous acid by Balard's process with 
oxide of mercury, is subordinate to the production of a bleach- 
ing chloride of oxide, for by agitating peroxide of mercury 
suspended in water, in a bottle filled with chlorine there is 
formed a soluble bleaching chloride of oxide of mercury, con- 
taining all the oxide, if an excess of it is not employed in the 
experiment and sufficient water is present. The distillation 
of this chloride should necessarily produce hypochlorous acid, 
even without the presence of an excess of chlorine; it is there- 
fore the most suitable of these compounds for the preparation 
of hypochlorous acid; for we have: 
2Ch 3 HgO = Ch 2 + Ch 2 HgHgO. 
, * , * , , » 
chloride of oxide. hypoch's acid, oxichloride of mercury. 
As the oxichloride of mercury is almost insoluble, it may 
happen that, during the preparation of the chloride of oxide 
of mercury by the process described above, especially if a 
small quantity of water be used, and there be sufficient oxide 
* Ann. de. Chim. et de Phys. vol. 57, p. 266. f Ibid, vol. 57, p. 296. 
