1903.] P. C. Ray — Dimercurammonium Nitrate. 5 



The nitrate thus obtained is a white amorphous powder ; it retains 

 moisture, which is not driven off even when the salt is dried in the steam- 

 oven. It approaches closely to the formula 2NHg 2 NO s 4-H 2 0. 



Analysis. — The analyses given below are of distinct preparations : — 



Table of Analyses. 



% Mercury % Nitrogen % Water 



2 NHgjjNOg + H a O requires ... 82-47 577 1-86 



r83'13 602 



Found 1 82-71 5-92 



L82-48 



NHg 2 N"0 3 requires 84-03 5"88 



Behaviour. — When heated in a bulb tube the salt decomposes, with- 

 out fusion, with a sudden puff, giving off nitrous fames, mercury, and 

 water, and leaving a reddish yellow residue, consisting mainly of mer- 

 curic oxide. 



u Mercuroxy"-ammonmm Nitrate. 



Preparation. — To a moderately strong solution of mercuric nitrate 

 containing the minimum amount of the free acid dilute ammonia solu- 

 tion was added with constant shaking till there was a persistent smell 

 of ammonia. A bulky, flocculent, very pale yellow precipitate was obtained, 

 which was thrown on the filter-paper, washed and dried in the steam-oven. 

 The filtrate, though smelling distinctly of ammonia, gave on testing 

 indications of the presence of notable quantities of mercury. 



Analysis. — Prep. I. In this, the preparation was washed with cold 

 water:— Hg = 83. 20%. 



Prep. II. In this case, the preparation was washed with hot water. 

 Hg= 82.99 %(a), 83.03 %(&) ; N = 5.6 %. 



Prep. III. The dry substance was digested with nitric acid, the 

 acid decanted off, and the substance dried once more as above. The 

 colour was found to change from pale yellow to perfectly white. Hg = 

 83.2%;N = 5.9%. 



The identity of all the above preparations, as far as analysis goes, 

 seems to be established. 



Behaviour. — All the above samples when heated in a bulb-tube 

 decomposed with a sudden puff, giving off nitrous fumes, and yielding a 

 mirror of mercury, the residue mostly of mercuric oxide. It was, how- 

 ever, distinctly noticed that moist are was on the stem of the tube. 



