THE IMIDES OF THE AROMATIC SULPHONIC ACIDS. 23 



Barium dibenzenesulphimide, {(C6H5S02)2N}2Ba+2H20, crys- 

 tallises from water in fine needles, freely soluble in water when 

 hot, but less so when cold, one part of the salt dissolving in 

 about twenty seven parts of water at lo.6°C. Two separate 

 preparations were analysed with the following results : — 



This compound sometimes forms microscopic prisms, containing 

 no water of crystallisation. Two such preparations gave the 

 following results on analysis : — 



Found Calculated 



(1) (2) 



Barium 18.85 18.29 18.83 



Sulphur 17.21 17.75 17.57 



Nitrogen 3.79 3.89 3.85 



Preparation (1) was obtained by the spontaneous decomposition 

 of dibenzenesulphohydroxylamine in an aqueous alcoholic solution. 

 Preparation (2) was obtained in one of the experiments, in which 

 dibenzenesulphohydroxylamine was reduced by sulphur dioxide in 

 presence of aqueous alcohol and the resulting liquid was concen- 

 trated, after neutralisation with barium hydroxide. That these 

 preparations differed from the previous ones only in containing 

 no water of crystallisation was ascertained from the fact that the 

 melting point of the free imide prepared from both was found 

 to be identical, namely 157°C. 



