A solution thus prepared has the following properties:—
Ammonium sulphide; white precipitate of hydroxide.
Potash or soda; white precipitate, soluble in excess.
Ammonia; white precipitate, only slightly soluble in excess.
There is also a blowpipe-test: if a little of the hydroxide be collected, moistened with cobalt nitrate, and heated on charcoal by the oxidising flame, alumina, under these circumstances, becomes of a blue colour.
5. URANIUM.
§ 900. Uranium.—The salts of uranium are intensely poisonous. The nitrate of uranium is used in photography and the arts, and is a common reagent in chemical laboratories.
According to Kowalewsky,[977] the acetate of uranium possesses an unusual power of uniting with albumin; the other soluble uranium salts act also in a similar way. Hence concentrated solutions of uranium salts corrode the mucous membranes, transforming, for example, the walls of the stomach into a dead uranic albuminate. If a non-corrosive salt of uranium is injected subcutaneously, glycosuria is produced, with fatty degeneration of the walls of the blood-vessels, and fatty changes in the kidneys, liver, &c. The animal wastes and ultimately dies; 0·5 to 2·0 mgrms. of UO3 per kilogrm. will kill a cat, dog, or rabbit, if injected subcutaneously. The nitrate or acetate, when given by the mouth, produces gastro-enteritis and nephritis, with hæmorrhages in the substance of the kidney. Uranium is not used in medicine.