142 Scientific Intelligence. 
Oxidation with iodine, bromine and potassium permanganate were 
resorted to. Iodine seems to have no action upon hyponitrous 
acid either free or combined; but bromine produces a character- 
istic reaction : 
g,N,0,+(H,0),+Br,,=(HNO,),+ (HBr), + Ba 
8 ction of permanganate is irregular unless a large excess 
sulphuric acid be employed; the oxygen absorbed is pes oigtl 
per cent omeparpaes to three equivalents. Nitrogen monoxide 
is produced as follo 
Ag,N, G-rauae O=N,0+ (HNO,), +(Ag20)>. 
The silver oxide unites with the sulphuric acid. The heat of 
Job agwan of silver hyponitrite was determined by oxidizing it 
bromine water. Five calorimetrical experiments made be- 
ees 12° and 14° gave 29: 65 calories, From this the value 
—9°3 calories is Ang Ree as the heat absorbed by N, + Ong+Ago> 
and —16°3 calories for N, +0 Zo For the acid itself the 
heat evolved in "the reaction of dilute hydrochloric acid upon 
silver hyponitrite pee measured, and from it the heat of formation 
was calculated as 38°6 calories. It is formed from its elements 
then with Sean of heat; whence its instability. 7 - 
Chim. II, xl, 401, , November, 1883 
n certain ew Compounds ‘of Silver.—In 1879, * awed 
g on the fact i a 
ach 
this reaction. The silver ei sity euit. ae have, investigated 
weights of silver nitrate and water—and then the reaction is given 
by hydrogen yg ei phosphide and antimonide as well as ar 
senide. With hydrogen sulphide a yellow to yellowish greed 
spot appears, haha Hee by a black edge, the whole becoming 
place. The on ‘shows a distinct y acid reaction. To isolate 
the yellow compound, H,S was passed into a concentrated solu- 
tion of silver nitrate "until the escaping gas blued a solution of 
iodide of zinc and starch. A yellowish-green precipitate W* 
produced, isele washed with ee _ acid and dried in the 
air, apie darker in color, and o alysis gave the formula - 
- (Ag,S.AgNO,). Its formation is en: in the equation : 
(AgNO,), +H,S=(Ag,S.AgNO,) +(HNO;),. 
On gently heating it decomposes thus : 
(Ag,S.AgNO,),=(NO,), + Ag, + (Ag,S); + Ag2504- 
This compound is obtained also by treating silver sulphide with 
fuming nitric acid. But if the nitric acid have a specific gravity 
of 1:18, a violet-brown kermes-colored powder is also obtained. 
This latter body is also produced by heating in a water a 
solution of 40 parts silver nitrate and 35 parts of water and adding : 
bath @ 
