Magnesium carbonate (MgCO3)-Powder

Characteristic

Magnesium carbonate, MgCO₃ (archaic name magnesia alba), is an inorganic salt that is a white solid. Several hydrated and basic forms of magnesium carbonate also exist as minerals.

Chemical formula:MgCO₃

Molar mass:84.3139 g/mol (anhydrous)

Appearance:white solid   hygroscopic

Odor:odorless

Density:2.958 g/cm³ (anhydrous)   2.825 g/cm³ (dihydrate)   1.837 g/cm³ (trihydrate)   1.73 g/cm³ (pentahydrate)

Melting point:350 °C (662 °F; 623 K)  decomposes (anhydrous)   165 °C (329 °F; 438 K) (trihydrate)

Solubility in water:anhydrous:  0.0139 g/100ml (25 °C)  0.00603 g/100ml (100 °C)  Solubility product (Ksp)

10−7.8

Solubility:soluble in acid, aqueous CO2  insoluble in acetone, ammonia

Magnetic susceptibility (χ):−32.4·10⁻⁶ cm³/mol

Refractive index (nD):1.717 (anhydrous)  1.458 (dihydrate)  1.412 (trihydrate)

Crystal structure：Trigonal

Application

The primary use of magnesium carbonate is the production of magnesium oxide by calcining. Magnesite and dolomite minerals are used to produce refractory bricks.MgCO3 is also used in flooring, fireproofing, fire extinguishing compositions, cosmetics, dusting powder, and toothpaste. Other applications are as filler material, smoke suppressant in plastics, a reinforcing agent in neoprene rubber, a drying agent, a laxative to loosen the bowels, and colour retention in foods. In addition, high purity magnesium carbonate is used as antacid and as an additive in table salt to keep it free flowing.

Magnesium carbonate is also used in taxidermy for whitening skulls. It can be mixed with hydrogen peroxide to create a paste, which is then spread on the skull to give it a white finish.

In addition, magnesium carbonate is used as a matte white coating for projection screens.