Characteristic:
Appearance and properties:white amorphous powder.
Relative density(water=1):5.85(20℃)
Melting point(℃):2680
Boiling point(℃):4300
Solubility:Insoluble in water,slightly soluble in hydrochloric acid,nitric acid and hydrofluoric acid.Dissolved in aqueous sulfuric acid and heat.