30 REDUCTION OF ALKALI NITRITE BY AN 



tive as this proved to be, of adding sodium hydroxide to a 

 concentrated solution of sodium nitrite I proceeded in two ways. 

 In one the amalgam was covered with a cold saturated solution 

 of sodium hydroxide, which is quite inactive upon it ; then the 

 concentrated solution of nitrite was slowly added. At first, the 

 alkali greatly impedes the action of the amalgam upon the 

 nitrite but with more of the solution of the latter added the 

 action goes on faster and to the end and gives the usual large 

 proportion of hyponitrite and very little hydroxylamine. In the 

 other way of testing the point, some concentrated solution of 

 sodium nitrite and sodium hydroxide was treated with some 

 amalgam ; then more sodium nitrite was added and then more 

 amalgam. The result was the same as before. My aim in thus 

 working was to have the effects, if any, of the most concentrated 

 alkali from the first, without having to deal afterwards with 

 too inordinate an excess of alkali, when the analysis had to 

 be made. 



I have also tried to ascertain the effect of lessening the 

 amount of alkali present. In acid reducing mixtures nitrous 

 acid becomes largely converted into hydroxylamine without 

 production of hyponitrous acid, so that it seems probable that 

 could the alkali formed in reduction of nitrite by sodium be 

 neutralised nearly as fast as produced, much hydroxylamine 

 would be got and very little hyponitrite. The use of the ordi- 

 nary acids for the purpose in such a way as to give conclusive 

 evidence on the point does not seem to be j^racticable, while 

 the great rapidity of the process of reduction makes the use of 

 carbon dioxide (Aschan, Ber., 1891, 24, 1865) very unpromis- 

 ing. I have, therefore, tried tbe effect of adding ammonium 

 acid carbonate along with the sodium nitrite, expecting the 



