1 822 .] Properties of Peroxide of Hydrogen . 51 



not brisk ; so that the deoxidizement requires some hours for its 

 completion. 



Oxide of irouy from the decomposition of water by hot iron. 

 Weak action upon the peroxide both concentrated and diluted. 

 Fifteen hours were not nearly sufficient to complete the deoxi- 

 dizement of the liquor ; for it was found after this time nearly 

 unaltered. 



Oxide of nickel f peroxide of copper, oxide of bisrriuth. The 

 action of true oxides upon the concentrated liquor is not very 

 strong, but it is sufficient to evolve all the oxygen in the space 

 of a )iesv hours, and in 15 hours they evolve it from the peroxide 

 -containing only one-ninth of its volume of oxygen. 



Potash, soda. Strong action even when they are dissolved in 

 water upon the concentrated peroxide of hydrogen ; rather rapid 

 evolution of oxygen ; very soon perfect deoxidizement. When 

 the peroxide of hydrogen is diluted with water, the decomposi- 

 tion takes place less rapidly, but eventually all the oxygen is 

 expelled. 



Gelatinous magnesia, and highly concentrated peroxide of 

 hydrogen. Very evident evolution of oxygen gas which gradually 

 subsides before the total deoxidizement. 



Gelatinous magnesia, and liquor containing nine times its 

 volume of oxygen. Rather brisk effervescence, which gradually 

 subsides before the deoxidizement is complete. It appears, 

 however, to evolve proportionally more oxygen when the liquor 

 is dilute than when it is concentrated. 



Magnesia in powder. The action is weaker than when in the 

 gelatinous state. 



Hydrate of harytes, strontian, and lime. But little action. 



Oxide of uranium, procured by decomposing sulphate of 

 uranium with potash. Still less action than the last oxides. 



Oxide of titanium in potvder, sublimed ooiide of zinc, oxide of 

 cerium. Weak effervescence. At the end of 30 hours the liquor 

 was scarcely deoxidized. 



Of the Oxides which evolve the Oxygen of the Peroxide of Hydro-- 

 gen, and lohich at the same time lose their own either partially 

 or totally. 



These oxides are the oxides of silver, mercury, deutoxide and 

 peroxide of lead, of gold, platina, and probably iridium, palla- 

 dium, and rhodium. 



Oxide of silver. Of all oxides this appears to have most 

 action upon the peroxide of hydrogen ; it immediately expels its 

 oxygen, and this occurs so rapidly, that explosion may 

 happen when the peroxide is concentrated : moreover, the 

 heat produced is such that luminous spots are perceived when 

 the experiment is performed in the dark. Under these circum- 

 stances, it is not extraordinary that the oxide of silver should be 

 reduced: the experiment should not be made in a narrow tube* 



e2 



