84 



L. F. NiLSON, 



This salt, when heated to 100°, loses 6 mol. of water out of 9 (calc. 

 12.23), and possesses a high theoretical interest in the same respect as 

 the preceding. 



SELENITES OF IRON — Fe 2 . 



l. 8 / 9 -Selenite: Fe 6 .0 17 .8SeO + 28H 2 0. 



An excess of neutral sublimated chloride of iron, also employed to 

 produce the following salt, was precipitated with selenite of sodium. The 

 precipitate was of a dirty yellow colour, voluminous, indistinctly cry- 

 stalline and very difficult to be washed. The mother-liquor held sele- 

 nious acid. 



Analyses: 



1) 0.6235 gr. salt gave 0.2073 gr. selenium or 0.2913 gr. selenious acid 

 and 0.1605 gr. oxide of iron. 



2) 0.555 gr. salt gave 0.1856 gr. selenium or 0.2608 gr. selenious acid 

 and 0.144 gr. oxide of iron. 



3) 0.707 gr. salt, heated to 100°, lost 0.152 gr. water. 



Represented in 100 parts: 



found calculated 



1. 2. 3. 



Oxide of iron .... 25.74 25.94 — 3Fe 2 3 480 25.64 



Selenious acid ... . 46.72 47. — 8Se0 2 888 47.44 



Water (loss) 27.54 27.06 21.50 28H 2 504 26.92 



100.00 100.00 1872 100.00 



Concerning this salt, which at 100° gives off 22 mol. of water (calc. 

 21.12 pr. ct), the same remark may be made in a theoretical point of 

 view, as in the case of the two preceding salts of chromium. 



2. Neutral: Fe 2 .0 6 .3SeO + 9H 2 0. 



Neutral chloride of iron was precipitated with an excess of selenite 

 of sodium. The precipitate exhibited the same appearance and properties 

 as the above-mentioned. 



