272 Mr. W. J. Sell. On a Series of Salts [Jan. 26, 



3. '1477 grm. (another sample precipitated by HC1) titrated with 



IT 



— AgN0 3 required 8*6 cub. centims. 



4. -4274 grm. ignited left '062 grm. Cr 3 3 . 



5. '5382 grm. crystallised salt dried by pressure lost at 104° 

 ♦05025 grm. H 2 0. 



Theory. 



Analysis. 









1. 



2. 



3. 



4. 



5. 







Percentage. 













144 



13-87 



13-85 











H 48 



48 



4'62 



4-70 











N 24 



336 















12 



192 















Cr 2 .... 



104 -8 



10-09 









9-94 





Cl 6 



213 



20-52 





20-48 



20-67 









1037 "8 















6H 2 .. 



108 



9-42 











9-33 





1145 8 















The Sulphate. 



This compound is readily obtained from the preceding, by the action 

 of silver sulphate. The silver chloride is filtered off, and the solution 

 concentrated at a gentle heat or in vacuo. If the warm solution of 

 the chloride be rubbed up in a mortar with the proper quantity of 

 silver sulphate, a crop of crystals of this compound is deposited after 

 nitration, on cooling, in short dark green prisms. The crystals have 

 the composition (CON 2 H 4 ) 12 Cr 2 (SO 4 ) 3 10H 2 O. 



The following results were obtained on analysis : — 

 1. '385 grm. salt, dried by pressure between bibulous paper, lost at 

 105° C. '0538 grm. water, and gave, when dissolved and the sulphuric 

 precipitated by BaCl 2 , '208 grm. BaS0 4 . 



Theory. Analysis. 

 Percentage. 



C 12 144 



48 



No 4 336 



Oi B 240 



Cr 3 104-8 



(S0 3 ) 3 240 18-56 18-54 



10H 2 O 180 13 92 13-98 



1292 -8 



