Dihydrate

Test and Method

Specification

Identification A (EP/BP)

A .Loss on ignition  19.0 – 23.0

Identification B (EP/BP)

Solution S gives reaction of sulfates

Identification C (EP/BP)

Solution S gives reaction of calcium

Solubility (EP)

Very slightly soluble in water, practically insoluble in ethanol 96 %.

Acidity or alkalinity (BP)

The solution is colourless. Add 0.2 mL of methyl red R. The solution is reddish-orange.

Chloride (BP/EP)

NMT 300 ppm

Iron (BP/EP)

Not more than 100 ppm

Arsenic (BP/EP)

Not more than  10ppm

Heavy Metals(BP/EP)

NMT 20 ppm

Loss on ignition (BP/EP)

Not more than 18.0- 22.0%, (1 g, 850*C, 1 hour).

Assay(BP/EP)

Contains not less than 98.0- 102.0% of  CaSO4.2H2O.