Sodium Tungstate
Introduction
Name: Sodium Tungstate
Formula: Na2WO4·2H2O
Molecular weight： 329.86 (Dihydrate)
293.86(No Hydrate)
Melting Point: 698℃
CAS: 10213-10-2
10213-10-2（Sodium tungstate dihydrate）
Water Solubility: Slightly alkaline
Appearance: Colorless crystal or white crystalline powder
Density: 4.179 g/cm3
Solubility (Water): 74.2g/100mL
Physical Property
A colorless crystal or white crystalline side ramps, soluble in water, aqueous solution is slightly alkaline; slightly soluble in ammonia, insoluble in ethanol. It will weathering in dry air, and lose crystal water to turn to anhydrous compounds when heated to 100°C.
Chemical Property
It turns to acid precipitation when in case of strong acid:
Na 2 WO 4 + 2HCl - Boiling → H 2 WO 4 ↓(Yellow) + 2 NaCl
Na 2 WO 4 + 2HCl + H2O → H 2 WO 4 • H 2 O ↓ (White) + 2 NaCl
The hydrogen sulfide inlet into sodium tungstate solution, the sulfur atom will substitute the oxygen atom one by one, and finally generate tetrathiocarbonate sodium tungstate.
Application
Used as the raw materials for preparing tungsten, tungstic acid and tungstate; also used as a mordant, catalyst and pigments, as well as fabric fire retardant and chemical analysis reagents; at the same time, it is widely used in petroleum, aerospace and defense industries.