Ammonium Paratungstate (APT) Physical & Chemical Properties
Physical and chemical properties of Ammonium paratungstate
Formula: H8N2O4W
Under different crystallization conditions may have the following formula：
(1)3(NH4)2O-7WO3-6H2O
(2)5(NH4)2-1 2WO3-5H2O
(3)5(NH4)2O-1 2WO3-5H2O
(4) 5(NH4)2O-1 2WO3-1 1H2O
Molecular Weight:283.9145
Appearance: white crystal, shape are two kinds of flake or needle.
Solubility: slightly soluble in water, while 20 ℃ solubility less than 2% in water, insoluble in alcohol. The Ammonium paratungstate will lose some ammonia and water of crystallization when heated to 220-280 ℃, can be converted as ammonium metatungstate. Will lose all crystal water and ammonia when heated to above 600 ℃, into completely yellow tungsten oxide.
Related Products:
0.6um yellow tungsten oxide is a kind of tungsten oxide, with a positive yellow powder appearance, stable properties at normal temperature and apparent density of 0.6-1.0g/cm3.
Ammonium metatungstate(AMT) is an important intermediate compounds of tungsten hydrometallurgical process, appearance is white crystalline powder, solubility in water is the largest in the tungsten compounds which over 300g WO3/100ml H2O (in 25℃).
Sodium tungstate, a tungstate of sodium, is useful as a source of tungsten. It is prepared from tungsten ores used to manufacture tungsten by reducing it.
Purple Tungsten oxide is divided into WO2.72 (or W18O49). It is a kind of tungsten oxide. It is abbreviated as VTO. It is a purple finely grained crystalline powder, and its color usually appears purple or blue purple.