Uranyl double chlorides

It may be prepared by dissolving any of the oxides or hydroxides of uranium in nitric acid and concentrating the solution or by double decomposition of uranyl chloride with silver nitrate. It crystallises in lemon-yellow prisms, the form of which varies according to the nature of the solvent. The crystals exhibit a yellowish-green fluorescence which does not increase, as is usually the case with phosphorescent substances, even at such a low temperature as —190° C. They also... 

Uranyl chloride, UOjClj, is formed by heating U02 to red heat in a stream of dry chlorine. It forms a yellow crystalline mass, which is hygroscopic and soluble in water. The water solution on slow evaporation forms a monohydrate. The anhydrous uranyl chloride is stable if it is kept away from moisture. The water solution has an acid reaction and upon heating liberates HC1. It forms double salts with the alkali chlorides, such as 2 KC1 UO2CI2 2 H2O. 

Uranyl solutions are easily prepared by dissolution of water-soluble salts the nitrate, fluoride, chloride, bromide, iodide, sulfate, and acetate. Other water-soluble uranyl salts Include those of other organic acids the formate, propionate, butyrate, emd valerate and certain double salts such as potassliun uranyl sulfate, sodium uranyl carbonate, sodium uranyl chromate, etc. Uranyl solutions may be prepared also by dissolution of a uranium(VI) compound in an appropriate solvent, by dissolution of a lower valence uranium compound in an oxidizing medium, or by oxidation of lower valence uranium ions already in solution. Uranyl solutions are yellow in color. They are the most stable of uranlvim solutions. As indicated in preceding paragraphs, the... 

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