Properties：Colorless transparent liquid,sweet taste,melting point< -18℃,boiling point 146℃,relative density 0.891 (20℃),refractive index 1.392 (20℃),flash point 35℃,convoluted with alcohol and ether,slightly soluble and decomposable in water.

Properties: Colorless transparent liquid,with odor of ester,boiling point 103 -105℃,relative density 0.9676 (20℃),refractive index 1.3773 (20℃),flash point 15℃,soluble in ethanol and ether and decomposable in water.

Properties: Colorless & inflammable volatile liquid,aromatic odor,melting point -80℃,boiling point 54.3℃,relative density 0.917(20℃),refractive index 1.3598(20℃),flash point -20℃,consulate in ethanol,ether, freely soluble in acetone,solubility in water 11.8g/100ml.

Properties: Achromatic crystal,density1.65g/m3,better hygroscopi- city,dissolved easily in the water,has corrosive characteristics.Melting poin 73℃,boiling point 200℃,relative density1.65.