360 On the Connexion of Catalytic Phcenomena with Allotropy. 



sulphuric acid, turns tincture of guaiacum to the deepest blue, 

 separates iodine from iodide of potassium, changes aqueous sul- 

 phurous acid immediately into sulphuric acid, a solution of yel- 

 low prussiate of potash into red, &c., and NO^ is eliminated in 

 these reactions. 



From these facts it is clear that the two equivalents of oxygen 

 which are taken up by the deutoxide of nitrogen act in many 

 cases just like oxygen allotropized by electricity or phosphorus, 

 on which account we may also assume that hyponitric acid js 

 nothing else than ozonized deutoxide of nitrogen, or NO^ + 20. 

 But if this assumption is admissible, it follows, further, that deut- 

 oxide of nitrogen possesses in a very high degree the property of 

 ozonizing oxygen. And since NO- not only transforms into 

 O, but also unites with this O as such, deutoxide of nitrogen may 

 be looked upon as the most decided exciter of oxygen {Sauer- 

 stofferrcger) and carrier of [O-trdger] ; and hence it is that it 

 plays such an important part in certain oxidizing processes; 

 for example, the conversion of SO^ into SO^ by means of 

 atmospheric oxygen. 



The first degrees of oxidation of manganese and iron are 

 distinguished by the readiness with which they are oxidized by 

 common oxygen to peroxide of manganese and peroxide of iron. 

 And of the oxygen united with the protoxide of manganese or of 

 iron, ^ it is well known that it comports itself in many cases like 

 the associated with NO-. Peroxide of manganese even alone 

 turns tincture of guaiacum blue, and peroxide of iron does so 

 when it is dissolved in an acid ; peroxide of manganese decom- 

 poses solution of indigo just as dissolved peroxide of iron does ; 

 peroxide of manganese oxidizes sulphurous acid ; peroxide of 

 iron and its salts do the same. In short, both these oxides com- 

 port themselves as oxidizing agents like hyponitric acid, for 

 which reason we may compare MnO and FeO to NO^, and con- 

 sider them, like this, as exciters of oxygen and carriers of O. If 

 protoxide of manganese or protoxide of iron were liquid or 

 gaseous instead of being solid, they would probably ozonize 

 common o^lygen as rapidly and energetically as NO^. 



Different from NO^, FeO, MnO in degree, indeed, but not in 

 kind, is the comportment of certain other metallic oxides ; and 

 in this respect we must notice oxide of barium, which, although 

 perfectly indifferent to common oxygen in the cold, unites with 

 it to form peroxide of barium at a moderately high temperature. 

 That the oxygen taken up by the BaO is in the O condition, 

 needs, I think, no further proof; and it is clear that BaO, like 

 NO", &c., can ozonize or allotropize common oxygen. It is 

 known that KO, NaO comport themselves quite similarly to BaO. 



Oxide of lead also, in the cold, is quite indifferent towards com- 



