A N T I M O N Y : ITS HISTORY, CHEMISTRY, MINERALOGY ...

THE CHEMISTKY OF ANTIMONY.
compound of stiboniuin. In a solution it can be ionised into SbR4
and I'.
Some other compounds are: Tetramethylstibonium chloride,
Sb(CH3)4Cl; tetraethylsliboniuni chloride, Sb(C2H5)4Cl; tetramethylstibonium
hydroxide, Sb(CH.i)4OH.
Antimony Trihaloids.—Antimony combines with the halogens
to form a series of characteristic compounds. For fluorine,
chlorine, and iodine there occur the tri- and pentahaloids ; and for
bromine only the trihaloid is known. The characteristic of the
trihaloids is the capability of being hydrolysed; and in water they
form insoluble oxyhaloids.
Antimony Trifluorides.—When metallic antimony is brought into
an atmosphere of fluorine, it burns, with the production of a white
solid fluoride, probably the trifluoride (Moissan). When antimony
trioxide is put into hydrofluoric acid and the solution is gradually
diluted, crystals of fluoride are deposited. As an amorphous mass,
it can be produced by dry distillation of antimony powder with
quicksilver'fluoride.
The trifluoride is dimorphous, and it crystallises generally in rhombic
octahedra, but sometimes also in prisms. According to Buff and Plato,
its specific gravity is 4*379 at 20'9°, and its molecular volume 40*3.
By mixing antimony trioxide and the carbonate of alkalies in
hydrofluoric acid, the following complex alkali-antimony fluorides are
obtained :—
Chemical
Formulae.
LiSbF4j LiF
NaSbF4, 2NaF
KSbF4
KSbF4.KF
NH4SbF4.NH4F
CsSbF4
C2SbF4.CsF
4C2SbF4.3SbF3
CsSbF4.SbF3
CsSbF4.2SbFa
Crystalline
Forms.
Crystallises with
difficulty.
Small prisms.
Large rhombic
octahedra or
prisms.
Leaf-like or in
plates.
Rhombic plates
or prisms.
Prisms.
Rhombic prisms.
Generally in
plates.
Needles.
Prisms.
1
Solubility
in Water.
>20
1 14
1 : 2'8
1 9 (at 13°)
1 < 2 (boiling-point!
1 0-9 (cold)
Remarks.
Becomes dull
in air.
Melts at 120°.
15
Observers.
Fliickiger.
JJ
Wells and
Metzger.
!