Tungstic acid Property

Melting point:

100°C (dec.)

Boiling point:

1473°C

Density 

5.5 g/mL at 25 °C (lit.)

refractive index 

2.24

Flash point:

1473°C

storage temp. 

Sealed in dry,Room Temperature

solubility 

insoluble in H2O, acid solutions; soluble in alkaline solutions

form 

powder

color 

Yellow to yellow-greenish

Specific Gravity

5.5

Water Solubility 

insoluble

Merck 

14,9818

Exposure limits

ACGIH: TWA 3 mg/m3
NIOSH: TWA 5 mg/m3; STEL 10 mg/m3

Stability:

Stable. Incompatible with strong oxidizing agents.

CAS DataBase Reference

7783-03-1(CAS DataBase Reference)

NIST Chemistry Reference

Tungstic acid(7783-03-1)

EPA Substance Registry System

Tungstate (WO42-), dihydrogen, (T-4)- (7783-03-1)

Safety

Risk Statements 

36/37/38

Safety Statements 

24/25

WGK Germany 

3

RTECS 

YO7840000

TSCA 

Yes

HS Code 

28259011

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P271Use only outdoors or in a well-ventilated area.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P302+P352IF ON SKIN: wash with plenty of soap and water.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

Tungstic acid Chemical Properties,Usage,Production

Physical Properties

Yellow amorphous powder; density 5.59 g/cm3; decomposes at 100°C; insoluble in water and most acids; soluble in hydrofluoric acid, caustic alkalies and ammonia solution. Freshly prepared tungstic acid containing a molecule of water of crystallization is moderately soluble in water.

Uses

Tungstic acid is used in preparing tungsten metal and many tungsten compounds. Also, it is a mordant for textiles.

Preparation

Tungstic acid is obtained as an intermediate in the recovery of tungsten from its minerals, scheelite and wolframite (See Tungsten). Also, the tungstic acid may be prepared by heating sodium tungstate with sulfuric acid or hydrochloric acid:
Na2WO4 + 2HCl → H2WO4 + 2NaCl
Na2WO4 + H2SO4 → H2WO4 + Na2SO4

Chemical Properties

light yellow powder

Physical properties

Yellow amorphous powder; density 5.59 g/cm³; decomposes at 100°C; insoluble in water and most acids; soluble in hydrofluoric acid, caustic alkalies and ammonia solution. Freshly prepared tungstic acid containing a molecule of water of crystallization is moderately soluble in water.

Uses

Tungstic Acid is used as a starting material in the synthesis of polynanocomposite material and polycrystalline ceramics.

Definition

ChEBI: Tungstic acid is a tungsten coordination entity. It is a conjugate acid of a hydrogentungstate.

General Description

Tungstic acid may be prepared by either digesting tungstate of lime or by treating tungsten with hydrochloric acid. 1

Flammability and Explosibility

Not classified