AMMONIA NITBATE WITH AMMONIA. 
367 
remain constant during the dissolution of a salt in it, of the nitrate having in concen- 
trated solutions a greater, and in dilute solutions a less volume than it has in the solid 
state, disappears by supposing that while the salt always undergoes during solution the 
contraction in volume so evident when the proportion of water is large, the water 
undergoes slight dilatation : for then it follows that when the salt is dissolved in only 
a small quantity of water, the former will experience a less contraction and the water a 
greater expansion, and that thus there may be a total increase in volume ; while when 
the salt is dissolved in a large quantity of water, the contraction of the salt will be in 
marked excess of the expansion of the water, and therefore will become evident in the 
increase in total volume. Dilute solutions of sodium carbonate and of some sulphates, 
having a less volume than the total water they contain, appear to afford an argument 
against the above supposition ; but in these solutions the salts dissolved are not the 
anhydrous ones, but those with water of crystallization. 
By dissolving ammonia nitrate in concentrated ammonia-water, the latter is affected 
in the same way as it would be by dilution with water, so far, that is, as the tension of 
the ammonia diffusing from its surface is concerned. 
9. The chemical behaviour of the liquid, like its physical properties, tends strongly 
to show that it is simply a solution of ammonia nitrate in liquefied ammonia. As a 
solvent, it appears, from the brief abstract as yet published of Mr. Gore’s experiments*, 
to resemble ammonia liquefied by pressure. But the ammonia nitrate modifies the 
solvent action of the ammonia in the same way that it does that of ammonia in aqueous 
solution. Its chemical properties are interesting, but in most instances such as might 
he expected in a mixture of ammonia nitrate and ammonia in the absence of ivater. 
The general effect of the liquid upon salts appears to be to convert them into ammo- 
niated nitrates and ammonium salts of the stylous radicals. 
As, however, a quantitative examination of the products would be attended with 
considerable difficulties from the nature of the liquid and the decomposition of the pro- 
ducts by water, only a qualitative one has been attempted. 
Bromine acts very energetically on the liquid, instantly dissolving in it without colour 
and liberating nitrogen. Ammonia hydrobromide is formed, and much of it deposited. 
No br ornate is produced. 
Chlorine has not been tried. 
Iodine dissolves slowly, but to a considerable extent, in the liquid, with evolution of 
heat. No gas is generated. A very little of the iodine dissolves without imparting 
any colour, but the after portions colour it until it becomes of a rich, deep brown-red, 
and almost opaque. Very early during the dissolution of the iodine a crystalline 
deposit, apparently white, begins to form, and this continues to be produced until it 
renders the whole nearly solid. No diniodamine is formed. The iodine seems, there- 
fore, to dissolve in the liquid either simply or in the form of Millon’s compound — 
N 2 H 6 1 2 *. Treated with water it yields nitrate and a little hydriodide in solution, and 
* Proc. Boy. Soc. xx. p. 441. f Ann. Ckim. Phys. lxix. p. 78. 
3 C 2 
