186 



FLUORESCENCE OF THE URANYL SALTS. 



peratures, because the spectrum of the 1 to 1 acid solution persistently 

 shifts toward the red instead of reverse shifting at 100 (see fig. 91). 

 The frequency interval remains unchanged, with a proportionately 

 large acid dilution. 



TABLE 110. Uranyl sulphate in sulphuric acid. 



TABLE 111. Uranyl sulphate in sulphuric acid. Frequencies and average intervals of 



fluorescence bands. 



URANYL POTASSIUM SULPHATE IN WATER. 



The spectra of the aqueous solutions of uranyl potassium sulphate, 

 like those of uranyl sulphate, consist of a single series of bands. 



The temperature shift of the more concentrated solutions, e, g., the 

 1/15 and 1/150 normal, is at first toward the violet, followed by a 

 reverse shift toward the red. The wave-lengths of the bands of the 

 aqueous solutions are recorded in table 112. It will be seen that the 

 shift toward the red is more marked than in the uranyl sulphate solu- 

 tions. (See also fig. 92.) 



