Researches on the Salts of Selenious Acid. 



47 



the first, on adding ammonia to a solution obtained by dissolving glu- 

 cina in selenious aeid, the solution being- continually kept strongly sour; 

 the second, on adding such a solution, treated with ammonia as long as 

 the precipitate formed was again dissolved, to semisulphate of glucinum; 

 and the third, when the mother-liquor from the second was treated with 

 acetate of sodium. The last mentioned is, however, regarded by him with 

 some diffidence. Neutral selenite of glucinum he has not obtained; he sta- 

 tes, regarding it, that it does not seem to be crystallizable, and that its 

 solution is decomposed with water, depositing basic salts. 



The following selenites of glucinum have been examined by me: 



l. % -Selenite 1 ): Be 5 .0 7 .2SeO + loH 2 0. 



By adding neutral selenite of sodium to a very dilute solution of 

 neutral sulphate of glucinum, a precipitate was obtained, which at first, on 

 stirring, was once more dissolved, but on adding more selenite of sodium 

 became permanent. If so much selenite of sodium has been added, that no 

 more glucina exists in the solution, there will be found in the mother-liquor 

 a considerable quantity of selenious acid in the form of acid selenite of 

 sodium, without the solution's becoming turbid on adding sulphate of glu- 

 cinum — all signs that the precipitate formed was basic. 



Analyses : 



1) 0.421 gr. salt gave 0.1292 gr. selenium or 0.1815 gr. selenious acid 

 and 0.1 gr. glucina. 



2) 0.2433 gr- salt gave 0.0745 gr. selenium or 0.1047 gr. selenious acid 

 and 0.0563 gr. glucina. 



3) 0.2515 gr. salt lost at 100° 0.0345 gr. of its weight. 



Calculated on 100 parts: 



experiment theory 



1. 2. 3. 



Glucina 23.75 23.14 — 5BeO 126 23.86 



Selenious acid. . . 43.12 43.03 — 2Se0 2 222 42.05 



Water (loss) . . . 33.13 33.83 13.72 10H 2 O rSO 34.09 



100.00 TOO^OO 528 100.00 



') As regards the terminology here employed in denominating the basic salts, 

 it is to be observed, that the amount of acid contained in the basic as compared 

 with the neutral salt is indicated by a fractional number. Such a terminalogy being 

 adopted for the acid salt, consistency seems to me to require its extension also to 

 the basic salts, and indeed it appears to me the only appropriate nomenclatur. 



