04 



W. Gibbs and F. A. Genth 



Strong sulpKuric acid dissolves t"he sulpTiate to a red oi 



liquid, but little deutoxyd of nitrogen being given off. The a 

 dition of water to this solution causes a violent effervescence 

 from the escape of deutoxyd of nitrogCD, and probably nitrons 

 acid. There remains a red liquid consisting chiefly of the double 

 sulphate of cobalt and ammonia, but almost always containing 

 a little acid sulphate of Purpureocobalt Even very dilute sul- 

 huric acid readily decomposes sulphate of Xanthocobalt by 

 oiling. Long boiling with chlorhydric acid also decomposes 

 this salt, the products of the decomposition being, as already 

 stated, chlorid of Purpureocobalt, free sulphuric acid, and deut- 

 oxyd of nitrogen. 



Sulphate of Xanthocobalt has the formula 



NOa.SNH 



as 



20*69 per cent cobalt. 

 20-68 



28 16 



27 65 



556 



5-68 



4< 



<l 



« 



<l 



M 



0-5776 grs. gave 0*3142 grs. sulphate of cohalt 

 0*6630 grs. gave 3060 grs. " « 



1'2S70 grs. gave 1-0150 grs. sulphate of baryta 



1'1472 grs. gave 9242 grs. " " 



0-7713 grs. gave 0*3868 grs. water 



0-4468 grs. gave 0*2285 grs. > " 



0-6020 grs. gave 169-48 c. c nitrogen at 14^ C. and 769'™'™-61 (h 



C.C., at 0^ and 760^^"» = 29-37 per cent. 

 1*2624 grs. gave 300 c.c. nitrogen at 5° C, and 775'"'»-20 (at 5°'3 C.) 



c. c, at O*' and 760'"''* = 29-51 per cent. 



The formula requires 



Eqs. 



Cobalt, _ 2 



Sulphuric acid, 2 

 Hydrogen, 16 



Nitrogen, 6 



Oxygen, 1 2 



Bulphuric acid, 

 hydrogen. 



^Imm)=\i0'%^ 



296-68 





Calculated. 



Mean. 



Foi 



ind. 



59 



20-55 



20*68 



20-69 



20*68 



80 



2794 



2790 



27-65 



28-16 



16 



567 



662 



656 



6*68 



84 



29-26 



29-44 



29-37 



29-61 



96 



16-68 



16*30 





4 



335 



10000 



A solution of snlphnroxis acid dissolves snlphate of Xantho- 

 cobalt without decomposition. On boiling, however, a complete 

 decomposition takes place, bubbles of gas are given off, and 

 there remains a red solution of the double sulphate of cobalt 

 and ammonia. The gas which is evolved produces no red va- 

 pors on contact with the air, and is probably protoxyd of nitro- 

 gen. The sulphate of Xanthocobalt is also decomposed by boil- 

 ing with urea, an abundance of a colorless gas without odor 

 being given off. The reactions of the sulphate are similar to 

 those of the chlorid. 



KITEATE OF XANTHOCOBALT. 



The nitrate of Xanthocobalt may be prepared like the sul- 

 phate, by passing a current of NOi into an ammoniacal solution 



cobalt 



formation of the nitrate goes 



