20 REDUCTION OF ALKALI NITRITE BY AN 



has been in recent years attributed to Maumene. It will suf- 

 fice here to say that this veteran French chemist has, it so 

 happens, published, in another connection, that he had not 

 experimentally investigated the reduction of nitrites in solution, 

 and that, far from laying claim to the discovery of hyponitrites, 

 he at first denied its truth on theoretical grounds. {J. Ch. Soc, 

 1872, 25, 772 ; Chem. News, 25, 153 and 285). 



Nitrous oxide, nitrogen, hydroxylamine, ammonia, sodium 

 hyponitrite, and sodium hydroxide (from the nitrite as well as 

 from the metal) are the substances always all produced, accord- 

 ing to my experience, in the reduction of sodium nitrite or 

 nitrate by sodium amalgam, but in proportions which greatly 

 vary within well marked limits. Nearly one-sixth of the nitro- 

 gen can be obtained as sodium hyponitrite in one way of 

 working or scarcely any at all in another. So, too, the range 

 of production of hydroxylamine is from nearly 9 per cent, of 

 the nitrogen of the nitrite down to a third per cent. The pre- 

 sence of ammonia may be very strongly manifest or be hardly 

 perceptible and escape notice. The two gases, nitrous oxide and 

 nitrogen, together represent at least 80 per cent, of the total 

 nitrogen and may vary between themselves to the extent of 

 either of them being nearly absent. Necessarily all the sodium 

 not left as hyponitrite appears as hydroxide, along with that 

 derived from the metallic sodium used as the reducing agent. 

 So long as any nitrite remains, no hydrogen appears among 

 the products, unless a very large quantity of water is })resent, 

 while when there is exceedingly little water hydrogen is not 

 formed even after all nitrite is gone. 



Within the limits indicated, the proportioning of the jn-o- 

 ducts of the reduction is well under control. The concentra- 



