Definition

Hydrated basic magnesium carbonate.

Content：40.0 per cent to 45.0 per cent, calculated as MgO .

Appearance ：White powder.

Solubility： Practically insoluble in water. It dissolves in dilute acids with strong effervescence.

Identification ：

A. 15 g has an apparent volume  before settling of about 180 ml.

B. It gives the reaction of carbonates .

C. Dissolve about 15 mg in 2 ml of dilute nitric acid R and neutralise with dilute sodium hydroxide solution R. The solution gives the reaction of magnesium .