4«6 On the Solutions of Mtrcury. 



ment of nitrous gas ; after which folution then takes place quietly, the oxigenated nitrate, 

 which was firft formed, being decompofed by the portion of mercury which remains. 

 The nitric folution of mercury made by heat, cannot keep all the oxide of mercury in 

 folution, except by means of an excefs of acid. 



Muriate of foda precipitates the nitric folutions of mercury, and affords muriates which 

 differ according to the degrees of oxigenation of the mercury in its folutions. 



Though the oxides of mercury, when too much oxigenated, cannot remain combined 

 with the fulphuric and nitric acids, It is not the cafe with refpefl: to the muriatic acid 

 which, not being faturated with oxygen like the two former diffolves mercury, and the 

 other metals at every degree of oxidation. Thus mercury combined with that acid in the 

 oxigenated muriate, is much more oxided than in the moft highly oxided of its nitric 

 combinations. 



Bayen has proved, that moft of the precipitates of mercury contain a fmall quantity 

 of acid. Citizen Berthollet has added new experiments to thofe already made by this 

 chemift. 



When a muriatic folution of mercury is precipitated by carbonate of foda, an examina- 

 tion of the precipitate, and of the fupernatant fluid, proves that the latter contains the 

 alkali with a great part of the carbonic acid, muriatic acid, and a fmall quantity of oxide 

 of mercury. The precipitate is formed of oxide of mercury, muriate of mercury, and 

 carbonate of mercury. When carbonate of pot-afli is ufed, the precipitate feizes all the 

 carbonic acid, and a greater portion of the muriatic acid ; fo that it fublimes almoft totally 

 in mercurial muriate. The precipitate contains lefs muriatic acid, if the carbonate of 

 pot-a(h which is ufed contains pure pot-afh. 



Bayen had alfo remarked, that certain precipitates of mercury poffeffed the property of 

 detonating when mixed with fulphur, but he has not explained this phsenomenon, and the 

 circumftances under which it prefented itfelf. Citizen Berthollet has fliewn, that fulphur 

 in contaft with the oxides of mercury, fuddenly takes from them the flightly adhering 

 oxygen, when thefc precipitates contain only a fmall quantity of muriatic acid ; but this 

 cffe£l cannot take place when the oxide of mercury is defended from the adion of the 

 fulphur by too large a quantity of muriatic acid. 



^ Chemical 



