80 



L. F. Nilson, 



a diselenite. At the ordinary temperature no complete solution took place, 

 on account of which the mixture was gently heated and then afforded, un- 

 der concentration of the acid, a gummy mass, which, on adding cold water, 

 separated a crystalline salt. The mother-liquor reacted strongly sour. 



Analyses: 



1) 0.70G5 gr. salt gave 0.3522 gr. selenium or 0.4949 gr. selenious acid 

 and 0.1047 gr. alumina. 



2) 0.6505 gr. salt gave 0.325 gr. selenium or 0.4566 gr. selenious acid 

 and 0.0965 gr. alumina. 



4) 0.5495 gr. salt gave off 0.01 gr. water at 100°. 



Represented in 100 parts: 



found calculated 



1. 2. 3. 



Alumina 14.82 14.83 — 2AR0 3 206 14.50 



Selenious acid . . . 70.05 70.19 — 9Se0 2 999 70.30 



Water (loss) . . . . 15.13 14.98 1-82 12H 2 216 15.20 



100.00 100.00 1421 100.00 



4. Diselenite : Al 2 .0 6 .3SeO. + 3H 2 .0 2 .SeO + 2H 2 0. 



This salt was formed und the same circumstances as the sesquisele- 

 nite, excepting that it was treated with such a quantity of anhydride as 

 was necessary in order to obtain a tetraselenite, or 210.64 pr. ct; it exhi- 

 bited also the same appearance and properties as the preceding. 



Analyses: 



1) 629 gr- salt gave 0.345 gr. selenium or 0.4848 gr. selenious acid and 

 0.071 gr. alumina. 



2) 0.6395 gr. salt gave 0.3515 gr. selenium or 0.4939 gr. selenious acid 

 and 0.0723 gr. alumina. 



3) 0.6375 gr. salt parted at 100° with 0.0325 gr. water. 



Centesimally represented: 



found calculated 



1. 2. 3. 



Alumina 11.29 11.31 — A1 2 3 103 11.99 



Selenious acid. . . . 77.08 77.23 — 6Se0 2 666 77.53 



Water (loss) 11-63 11-46 5.10 5H 2 90 10.48 



100.00 100.00 859 100.00 



