250 HYDROGENATED COMPOUNDS OF NITROGEN. 



or for each fixed equivalent of oxygen (8 grms.), 371, 261, 

 201, 19-8. 



10. Action of dilute alkalis. 



The reaction of the alkalis upon the salts of hydroxylamine 

 is worthy of notice. Dilute alkalis confine themselves to dis- 

 placing the hydroxylamine, at least in an operation of short 

 duration. The measurement of the heat given off shows that 

 hydroxylamine is a much weaker base than baryta, potash, and 

 even ammonia. In fact, with dilute potash and the hydro- 

 chloride it was 



2NH 3 OHC1 dissolved -f K 2 O dilute at 23, + 444 ; 

 with dilute baryta and the sulphate at 12'5 



2(KE 3 0)H 2 SOi dilute -f BaO dilute, 4- 7'8 ; 

 likewise with ammonia and the chloride 



]STH 3 OHC1 dissolved + NH, dilute at 12-5, + 3'35. 



These thermal measurements show that the displacement of 

 the hydroxylamine by the ammonia is complete, i.e. in pro- 

 portion to the weight of this base. It is the same even when 

 we employ only half the ammonia necessary for a complete 

 decomposition. 



Hydroxylamine is, therefore, one of the weakest of bases, 

 hence its salts offer a very pronounced acid reaction. 



It was found that the sulphuric acid, which is combined with 

 it, might be accurately estimated by an alkalimetric test; 

 almost like the soda in borax, but by an opposite test. 



11. The concentrated alkalis act very differently, for they 

 determine the decomposition of hydroxylamine itself. Thus 

 with concentrated potash we get destruction of the hydroxy- 

 lamine. 



12. Ammonia. 1. With a saturated aqueous solution of 

 ammonia at about zero, the hydroxylamine is displaced in its 

 salts without undergoing decomposition* even at the end of 

 several days. 2, With ammoniacal gas and solid hydro- 

 xylamine hydrochloride there is slow decomposition of the 

 hydroxylamine. Theory indicates that the displacement pro- 

 perly so called 



NH 3 OHC1 solid -|- NH 3 gas = NH 4 C1 solid + 1STH 3 O, liberates 



-f 12-6 - a, 



a being the heat of dissolution of NH 3 O, a compound which 

 appears to be liquid. 



In fact, it was observed that the dry hydrochloride absorbs the 

 ammoniacal gas immediately, in the proportion of one equivalent, 

 and even a little more. If we employ a considerable excess of 

 ammoniacal gas, working over mercury, and immediately remove 



