MICROCHEMICAL REACTIONS OF ANTIMONY 309 



Tetragonal. — Barium-antimony 1 tartrate (T or ( ) I . 



OrthorJiombic. — Yellow tri-iodide (O or M) ; ba- 

 rium-antimonyl tartrate; potassium-ant i- 

 monyl tartrate; sodium-antimonyl tartrate. 



Monoclinic. — Antimonyl chloride. 



Triclinic. 



DETECTION. 



A. By Means of Cesium Chloride. 



Apply reagent by Method 777, page 300, to the drop 

 strongly acidified with hydrochloric acid. 



A double chloride of cesium and antimony of the formula 

 2 CsCl-SbCl.3- 2\ H2O separates in hexagons and elongated six- 

 sided plates. Many of the hexagons show a system of straight 

 or curving ribs extending from the center to the angles of the 

 hexagons. 



Bismuth yields rhombs, prisms or long plates showing an 

 hexagonal outline, and having a lower solubility than the anti- 

 mony salt. 



Copper yields a series of double chlorides varying in color from 

 bright yellow to deep red depending upon the amount of copper 

 present. These salts usually separate in yellow rectangular 

 prisms or red acicular crystals, but the red compound sometimes 

 assumes forms closely resembling the iodo-compounds referred 

 to below. 



Tin causes the immediate precipitation of tiny regular octa- 

 hedra of the formula Cs2SnClo, a salt of chlorostannic acid. 



Cesium chloride has remarkable powers of forming more or 

 less difficultly soluble double chlorides with a large number of 

 elements and we may thus expect to often rind in preparations 

 to which cesium chloride has been added an abundant crop of 

 well-formed crystals, whose origin is puzzling unless we know 

 what elements are present. 



Given the proper concentrations we may expect cesium chloride 

 to form double chlorides with the chlorides of Cu, Mg, Zn, Cd, 

 Hg, Sn, Pb, Sb, Bi, Mn, Ni, Co, Fe. But no double cesium 



