432 M. Balard on the Nature of the [Dec. 



of hypochloric acid, as Thenard has suggested, to the com- 

 pound termed at present deutoxide of chlorine. 



HypO'Chlorites. — It is probable that the hypo-chlorites con- 

 tain chlorides mixed with them. But, as it might have 

 happened that the hypo-chlorous acid was formed by decom- 

 position, and was not present in the bodies from which it 

 was extracted, it was necessary to study its combinations 

 with the bases, and to show that they are similar to those 

 which exist in the decolourizing compounds. 



The hypo-chlorites may be obtained pure, by direct means, 

 or by double decomposition. 



Its direct combination with the bases is accompanied with 

 intense heat, which, when excessive, converts the hypo- 

 chlorite into chlorate and chloride. The presence of an 

 excess of base, however, prevents this change, while it is 

 very readily produced when the chlorous acid is in excess. 

 It is proper, therefore, to pour -upon the alkaline substance 

 acid insufficient for saturation, and to agitate the mixture 

 in a flask immersed in cold water. 



With these precautions hypo-chlorite of potash may be 

 formed ; if they are neglected, chlorate precipitates, and 

 oxygen is disengaged, mixed with chlorine if the heat is 

 intense. The latter appearance is easily explained, because 

 M. Morin has proved that the decolourizing compounds of 

 chlorine lose oxygen when they are changed into chlorates ; 

 and, it has been already stated, that the metallic chlorides, 

 when in contact with chlorous acid, undergo a decomposi- 

 tion in which chlorine is given out. Now, the formation 

 of chlorate is always accompanied with a corresponding 

 production of chloride. 



When the hypo-chlorites of barytes and lime have been 

 prepared, other salts may be formed by double decom- 

 position. 



Potash, soda, lithia, strontia, barytes, lime, and mag- 

 nesia, unite with it. 



M. Grouvelle had previously observed that the protoxide 

 of iron, oxygen of copper, and zinc, absorb this gas, and 

 form decolourizing compounds which are transformed by 

 heat into chlorine and oxides. 



Hypo-chlorous acid does not dissolve the slightest quantity 

 of peroxide of iron, when made to act on it, as in the decom- 



