Packaging and storage
Preserve in tight containers.
Loss on drying
731
Dry about 100 mg in a capillary-stoppered bottle in vacuum at 60

for 3 hours: it loses not more than 3.0% of its weight.
Residue on ignition
281
:
not more than 1.0%, the charred residue being moistened with 2 mL of nitric acid and 5 drops of sulfuric acid.