24 REDUCTION OF ALKALI NITRITE BY AN 



have done the same. But, for a long time now, I have felt 

 that most of the nitrous oxide and sodium hydroxide must 

 have another origin. Thuni has expressed himself in the same 

 sense, basing his opinion upon the comparative stability of 

 sodium hyponitrite in strongly alkaline solution, in which it 

 can be boiled with only gradual decomposition. This fact by 

 itself, however, is not quite inconsistent with the assumption 

 that the nitrous oxide and sodium hydroxide represent decom- 

 posed hyponitrite. But it does not stand alone ; there are other 

 facts which tell greatly against the probability of hyponitrite 

 being the source of most of the nitrous oxide obtainable by the 

 reduction of nitrite, (a) Hot concentrated solutions of nitrite 

 yield quite as much hyponitrite as cold ones, unless the tem- 

 perature is well above 100°, and even then the yield does not 

 fall off much, (b) In all cases the effervescence accompanying 

 the formation of hyponitrite goes on exclusively at the surface 

 of contact with the amalgam. (c) Low production of hyponi- 

 trite is not attended with higher production of nitrous oxide. 

 All these facts are opposed to the view that the nitrite is all 

 reduced to hyponitrite in the first place ; so, too, is what fol- 

 lows. 



The proportions of the products of the reduction of the 

 nitrite vary greatly with the circumstances, but yet only within 

 well-marked limits. Thus, of the nitrite reduced there is from 

 a sixth, under one set of conditions, to almost a fifth, under 

 other conditions, which becomes partly hyponitrite and partly 

 hydroxylamine (and ammonia) ; while the rest becomes nitrogen 

 and nitrous oxide, one or the other predominating, even large- 

 ly, according to circumstances. So, too, in one extreme case, 

 nearly all of the one-sixth of the nitrite will change into 



