P. C. Ray — On Mercurous Nitrite. 



[No 1, 



sulphite, thoroughly washed with hot water, dried and re-washed Avith 

 carbon bisulphide, purified by being kept over mercury and re-distilled. 

 Unless the precipitate is treated once m >re with carbon bisulphide, the 

 result is apt to be too high. There is thus not much to choose between 

 these methods. Both, however, give satisfactory results when conduct- 

 ed with care and patience. 



Preparation I. — 08695 gram, substance gave 0'274 gram. " free " 

 mercury = 3T5 per cent. " free " mercury. 1'1895 gram, substnnce kept 

 over H 2 S0 4 in the dessicator ; July 27bh 1895. July 30th, wt. = 1184 

 gram.; after a month's stay in the dessicator, the wt. was constant = 

 1*184 gram. 1*18-1 gram, substance gave 0*3485 gram. " free " Hg, = 

 29*43 per cent, "free" Hg ; 0'246 gram. Hg 2 Cl 2 from the ous salt in 

 solution = 17-7 per cent. Hg. ; and 0422 gram. Hg 2 Cl 2 from the ic salt 

 = 30*27 percent. Hg. 



Preparation II. — 1*2865 gram, substance gave 0*3957 gram. " free " 

 Hg,=30'76 per cent.; 0*25 gram. Hg 2 Cl 2 from the ous salt = 16'5per 

 cent. Hg ; and 0*4645 gram. Hg 2 Cl 2 from the ic salt = 30*69 per cent. 

 Hg. 1*224 gram, substance gave 0*3575 gram. " free " Hg, = 29'2 per 

 cent.; 0*243 gram. Hg 2 Cl 2 from the ous portion = 16*86 per cent. Hg ; 

 and 0'437 gram. Hg" 2 Cl 2 from the ic portion = 30*31 per cent. Hg. 



Preparation III. — 1*611 gram, substance gave. 0*5025 gram, "free " 

 Hg, = 30'62 per cent.; 0*348 gram. Hg 2 Cl 2 from the ous salt = 17'8 

 per cent. Hg; and 0*5965 gram. HgS from the ic salt = 3133 per 

 cent. Hg. 



The results are presented here in a tabulated form for convenience 

 of reference. 





" Free " 



Mercury 



Mercury 



Total 







Mercury. 



in the 



ic Salt. 



in the 



ous Salt. 



per cent, of 

 Mercury. 





1. 



31*5 







... 





2. 



[29-43] 



30*27 



17-7 



78*67 



1 















•o 



3. 



30*76 



30-69 



16-5 



7795 





30 



4. 



[29-2] 



3031 



1686 



77-87 



o 



5. 



306*2 



3133 



17-8 



7975 



1 



J 



The percentage of " free mercury " in analyis ( 2) and (4) respectively 

 comes out too low. The cause of this has been already explained. 



