irYDROXYLA.MINi:-«,?-l)ISULriTON\TES. 9 



{o ho neulr:iliso(l with sodium carbonate. On exposure foi- a niglit 

 in the ice-chamber, almost all the sodium sulphate will crystal- 

 lise out and then the mother-liquor can be evaporated to get the 

 new salt. Like corresponding ,9,9-salt, this salt forms hard masses 

 firmly adhering to the sides of the vessel. These masses are 

 stellar or warty groups of microscopic thick rhombic plates. The 

 salt is exceedingly soluble in water, from which it can be nearly 

 all precipitated by alcohol. Two preparations of the salt were 

 analysed (I. and II) : 



I, .2201) gave .lolo sodium sulphate. 

 .1059 gave .2096 b.irium sul2)hate. 

 .0151 gave 20.45 cc. moist nitrogen 



at 17° and 75(5. 8mm. 



II. .2509 gave .1502 sodium sulphate. 

 .0959 gave .1910 barium sulphate. 



HOjNSoNa.j requires sodium, 19.43 ; sulphur, 27.02 ; nitrogen, 5.92 

 per cent. 



The trlsodium sail, (S03Na)ONNa(S03Na),2H20, is prepared 

 just in the same way as the tripotassium salt. It is obtained as 

 a crystalline powder. For determination of its molecular magnitude, 

 see p. 11. 



.1450 gave .1054 sodium sulphate. Sodium = 23.57 



.2269 required 7.56cc. N/lOhydrochloric 

 acid with methyl-orange as indicator. 



Alkalinity as sodium = 7.66 

 .3594 gave .5698 barium sulphate. Sulphur = 21.75 



H409NS2iSrao requires sodium, 23.41 ; alkalinity sodium, 7.8 ; 

 sulphur, 21.71 per cent. 



Diammonium salt, (SO3NH )ONH(S03NH4). — Ammonium 

 hydroxylarainetrisulphonate (this Journ. 19, Art. 15, 9 hydrolyses 



