2 70 Mr. W. J. Sell. On a Series of Salts [Jan. 26 



3. '1383 grm. by Gottlieb's process gave volumes of C0 3 and K 

 (nearly equal) weighing "034986 grm. and '0224591 grm. respec- 

 tively. 



4. '09505 grm. by Gottlieb's process gave volumes of C0 2 and -NT 

 (nearly equal) weighing '0252056 and '0154869 respectively. 



5. '2071 grm. fused with pure NaHO, acidified with HN0 3 , and 

 titrated with AgN0 3 , using ferric sulphocyanate as indicator, required 



17-85 ^AgN0 3 solution. 



6. *3471 grm. burnt in a current of air, the chlorine caught by a 

 column of pure lime and estimated gravimetrically, gave '428 grm. 

 AgCl. 



7. '3208 grm. ignited, the mixture of platinum and chromic oxide 

 dissolved, gave '09135 Pt determined as double salt with NH 4 C1 and 

 '02364 grm. Cr 2 3 from filtrate by precipitation with ammonia. 



8. '07973 grm. acidified with HC1, the Pt precipitated by H 2 S, and 

 the Cr 3 3 in filtrate after decomposition of body by boiling HN0 3 , 

 gave '0226 Pt and "0061 Cr 2 3 . 



9. '1543 grm. acidified with HC1, and the Pt precipitated by H 2 S, 

 gave after ignition in air '0446 platinum. 



10. '8408 grm. crystallised salt (dried by pressure) lost at 100° C. 

 -014 grm. H 2 0. 



The Chloride. 



This compound may be obtained from the original green body, or 

 from the dichromate, by treatment with water and lead chloride. The 

 lead chromate is filtered off, and from the filtrate the chloride is pre- 

 cipitated in fine silky needles by passing in hydrochloric acid gas. The 

 compound recrystallised from warm water is deposited in long bright 

 green prismatic crystals, having the composition 

 (COK 3 H 4 ) 12 Cr 2 Cl 6 6H 2 0. 



It is freely soluble in hot water, less readily in cold, the com- 

 pound being decomposed by boiling its solution. Its aqueous solution 

 is precipitated by potassium dichromate, the compound precipitated 

 being similar in every respect to the dichromate just described. It 

 also gives precipitates with platinic chloride and potassium ferro- 

 cyanide, but none with ammonia, until the compound has been 

 destroyed by boiling or otherwise. The compound is almost com- 

 pletely precipitated from its aqueous solution by the addition of 

 hydrochloric acid. 



The following results were obtained on analysis : — 



1. '7943 grm. salt gave on combustion '4036^ grm. C0 2 and 

 •3369 grm. H 2 0. 



2. '48795 grm. titrated with — AgN0 3 required 28'16 cub. centims. 



