78 



DIVERS AND HAGA. 



v>'as undetermined, except in the experiment above referred to. The 

 nitric acid was estimated by evaporating the salt with barium hydrox- 

 ide to expel ammonia, filtering ott' the barium imidosulphonate, 

 removing barium as carbonate, and then patting the concentrated 

 solution of sodium nitrate into the nitrometer. The result was low, 

 but that is hnrdlv to be wondered at. Water, in that preparation in 

 which it was present in any quantity, was estimated by heating the 

 salt in dried air, and the result can be only approximate, for slight 

 hydrolysis, fixing water, is hardly to be avoided. 



Calc. a. b. 



Sodium I'll 8-00 8-42 



Ammonium 12" 16 11*71 11 •37 



Sulphm- 21-62 21-62 22-08 



Nitric acid, XO3H. 21-28 19-08 — 



Water O-QO 



The preparation a was formed in presence of good excess of 

 ammonium nitrate, and h in presence of little more than enough of 

 it. The calculation is for HN(S03Am)o, NaNOs. 



Hydrogen sodiwn potassium imidosulphonate nitrate. 



T^he very sparingly soluble dipotassium imidosulphonate is hardly 

 affected by digestion with a cold dilute solution of sodium nitrate, and 

 w^hen dissolved in it by heating crystallises out again almost un- 

 chano-ed, l)ut when left in a concentrated solution of sodium nitrate it 

 removes this salt from it. Taking about equivalent quantities of the 

 salts, HN(S03K)2 : SISTaNOs, and leaving the solution of the nitrate 

 standing over the dipotassium imidosulphonate in a loosely covered 

 beîiker for some days, tVie latter gives place to a caked mass of crystal- 

 line irrnnules, appearing under the microscope homogeneous but \\\\h 



