Researches on the Salts of Selenious Acid. 



109 



but rather appear as sexivalent double-atoms; and it may be confidently 

 expected that the determination of the molecular weights of some among 

 their volatile compounds will confirm this conclusion. 



Among selenites of trivalent elements, only those of bismuth and 

 antimony have been examined; a description of them follows. 



SELENITES OF BISMUTH. 



1. Neutral: Bi a .0 6 .3SeO. 



Basic carbonate of bismuth being boiled with a solution of selenious 

 acid, this waterfree salt was formed in small, microscopical needles. 



Analysis: 



0.7555 gr. salt, on strong heating, gave a residue of 0.4423 gr. oxide of 

 bismuth, during the sublimation of 0.3132 gr. selenious anhydride. 



In 100 parts: 



experiment theory 



Oxide of bismuth. . 58.54 Bi 2 3 468 58.43 

 Selenious acid ... 41.46 3Se0 2 333 41.57 

 100.00 801 100.00 



2. Va-Selenite: Bi 2 .O fi .3SeO + H 2 .0 2 .SeO. 



Hydrate of bismuth, treated at the ordinary temperature with excess 

 of concentrated selenious acid, afforded a salt in prismatic crystals, gene- 

 rally united in leaf-like aggregates. 



An aly ses: 



1) 0.523 gr. salt, heated to whiteness, gave a residue of 0.266 gr. oxide 

 of bismuth. 



2) 0.4765 gr. salt gave in the same manner 0.243 gr. oxide of bismuth. 



3) 0.66 gr. salt gave 0.22 gr. selenium or 0.3091 gr. selenious acid. 



4) 0.8485 gr. salt gave 0.284 gr. selenium or 0.399 gr. selenious acid. 



5) 0.868 gr. salt lost at 100° only 0.0005 gr. of its weight. 



