400 Scientific Intelligence, 
verse is the case with some other substances. The different effects depend 
upon the agen molecular condition of each substance.— Com; 
fendus, xlvii, 
3. Done Si separation of arsenic from antimony and z 
Bunsen finds that oxyd of antimony is most ner disti gems hon an- 
timonic acid and antimonate of antimony (2SbOs= 3-+SbOs) even 
after strong ignition by diese heating with “toepdne acid after addi- 
tion of a little iodid of potassium. Under these circumstances oxyd of 
antimony is dissolved to a wales aa without separation of iodine; in 
the other two cases iodine is set free remains dissolved in the iodid of 
nough nitric acid of asc 142 to — it, and then gently heated 
til it vanishes, 
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2. 
o 
Ss 
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oo 
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os 
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from the other two he recommends adding & 
excess of an aqueous solution of salphurous acid to the solution of 
the three sulphids in sulphid of potassium. The liquid is to be digest 
in a water-bath, and then boiled until two-thirds of the water and all the 
Gian acid is driven off. The filtrate now contains all the arsenic as 
arsenous 
dissolves sulphid of arsenic, but not the sulphids of tin and antimony: 
0 separate arsenic 
acid, while the mass on the filter is entirely free from arsemic.— 
Ann, de Chemie und Pharm., evi, 1. 
_ 4. On the separation of alumina from iron.—Cuancet has cereal 
that when a solution of vol pia apes of soda is added to one of a 
a of iron, the 1 wee of the iron is reduced to the form of protoxyd, es: 
solution in the re of a double hyposulphite of soda and iron. 
wok s, such as alumina and sesquioxyd of chro- 
le compounds with hyposulphurous us acid. 
Sie 
