Features：transparent colorless crystals. A massive sheet, hammers or granular. 318.4 ° C melting point. Boiling Point 1390 ° C 2.13g/cm3 density. Hygroscopicity strong, and very soluble in water, melted when emit a lot of heat, stirring solution was strongly alkaline. Exposed air moisture absorption, finally dissolved into all viscosity liquids. Also soluble in ethanol, glycerol, soluble in acetone and ether. Highly corrosive and can damage fibers, organic tissue damage, high temperature corrosion steel can.