IMIDOSULPHONATES. gl 



of the barium, filtering off barium sulphate, and evaporating in a 

 desiccator. Minute, brilliant, orthorhombic crystals are obtained which 

 are moderately soluble in water. The salt is stable in the desiccator, 

 or in the open air in dry weather, but soon hydrolyses in a bottle. 

 In dried air it is stable even when heated considerably, but it hydro- 

 lyses in ordinary air at and above ]40°. Eapidly heated it decom- 

 poses suddenly into a cloud of barium sulphate. Its solution is acid 

 to litmus but neutral to methyl orange. 



Proceeding in almost the same way as that followed by us, 

 Woronin ol)tained apparently the same salt, but he gave to its com- 

 position a molecule of ammonia more, calling it hariiini snlpliamate. 

 Since our preparation contains a molecule of water, the determination 

 of l^arium and of sulphur .agrees with both fornuili\î — r)a(H2NSÜ3)2 

 ' sulphamate,' and l)aHN(;S03)o, OH^ imidosulphonate. 



Quantitative analysis and the properties of the salt agree with the 

 l^jrmula, BaHNCSO.,),, OH, 



Calc Found. 



Barium 41-51 41-67 41-65 



Sulphur 19-39 19-51 — 



In warm solution barium hydrogen imidosulphonate reacts with 

 mercuric oxide to form the double salt. 



Barium (luunouium iiiiidosulplioiiate. — By adding one molecule of 

 l:)arium hydroxide to one of triammonium imidosulphonate (' neutral 

 îimmonium sulphamate') Woronin observed the formation of a 

 'soluble' barium salt, with the evolution of ammonia. He made no 

 statement as to its composition. On adding Ijarium hydroxide 

 gradually to triammonium imidosulphonate until it nearly ceased to 

 o-ive a precipitate we obtained a very slightly soluble salt as a pre- 

 cipitate which was a Iwrium ammonium imidosulphonate. It was 

 not fully analysed, but- gave a percentage of barium of 41-87 while 



