1st. Compact, or dry nitrate of ammoniac, undergoes little or no change at temperatures below 260°.
2dly. At temperatures between 275° and 300°, it slowly sublimes, without decomposition, or without becoming fluid.
3dly. At 320° it becomes fluid, decomposes, and still slowly sublimes; it neither assuming, or continuing in, the fluid state, without decomposition.
4thly. At temperatures between 340° and 480°, it decomposes rapidly.
5thly. The prismatic and fibrous nitrates of ammoniac become fluid at temperatures below 300°, and undergo ebullition at temperatures between 360° and 400°, without decomposition.
6thly. They are capable of being heated to 430° without decomposition, or sublimation, till a certain quantity of their water is evaporated.
7thly. At temperatures above 450° they undergo decomposition, without previously losing their water of crystalisation.
II. Decomposition of Nitrate of Ammoniac; production of
respirable Nitrous Oxide; its properties.
200 grains of compact nitrate of ammoniac were introduced into a glass retort, and decomposed slowly by the heat of a spirit lamp. The first portions of the gas that came over were rejected, and the last received in jars containing mercury. No luminous appearance was perceived in the retort during the process, and almost the whole of the salt was resolved into fluid and gas. The fluid had a faint acid taste, and contained some undecompounded nitrate. The gas collected exhibited the following properties.—
a. A candle burnt in it with a brilliant flame, and crackling noise. Before its extinction, the white inner flame became surrounded with an exterior blue one.