OXIMIDOSULPHONATES OR SULPHAZOTATES. 79 



the acetate, and using concentrated solutions, the mixture in a few 

 hours becomes filled more or less with a soft mass of minute crystals 

 of a lead sodium salt (7). Using much less sodium salt the mixed 

 solutions, if not dilute, also remain clear, but very shnvh^ deposit 

 spherical crystalline hard grains of the salt 4. The motlier-liquor of 

 this salt i^recipitates with water. If less concentrated the mixed 

 solution? yield a precipitate at once, which however redissolves on 

 heating, while concentrating the mixture by evaporation on a water- 

 bath causes the precipitate in what were even dilute solutions, to 

 o-raduallv redissolve. Evaporation to drvues^, yields a o"um-like 

 mass soluble in a little water but decomposed by much. 



Normal potassium oximidosulphonate and also the Kg salt give 

 ari immediate precipitate with normal lead acetate, soluble in excess 

 of either mother-salt in strong solution, but the solution remains clear 

 for only a few moments and then gives a crystalline precipitate unlike 

 tlie flocculent and voluminous one first formed {j'f. Fremy). AVhen 

 the oximide salt is in excess the precipitate is G ; with the acetate in 

 excess it is 5. Xormal ammonium oximidosulphonate is like the 

 sodium salt in keeping clear ïov a long time after being mixed with 

 normal lead acetate when in moderately concentrated solution, and in 

 precipitating when largely diluted. Its behaviour has not been 

 further observed. 



The normal sodium saU and a basic lead acetate give no ])reci])i- 

 tate when the former is in the ]^roportion of one mol. or more to one 

 mob of hemihydroxy-lead acetate, even after a long time or upon 

 dilution with watei-. With the basic lead acetate in excess precipita- 

 tion of the normal hydroxy-lead salt (Î) is immediate. 



The normal ]wtassirnn salt in excess and in concentrated solution 

 remains clear for a very slioi-t time after being 7uixed with basic 

 acetate ; it then deposits a crystalline flocculent ]irer-ipitate rcdis^olv- 



