Boron Oxide is colorless powder or glassy crystal. It is hard and brittle, creamy on its surface, and smelless. Boron Oxide is stable under high temperature. In incandescent condition, this product will not revert by carbon. However, it can be reverted into Monomer-Boron by alkali metal, magnesium and aluminum. Boron Oxide will be the sticky liquid when it is at about 600℃. Besides, it can strongly absorb water in air, and then it generates boric acid. Boron Oxide also dissolved in acid, ethanol, hot water; and it only slightly dissolved in cold water. Further, Boron Oxide can compound with many metal oxides to form special colorful borosilicate glasses. In addition, this product completely dissolved in alkali metal, copper, silver, lead, arsenic, antimony and bismuth oxides.
The density of crystalline boron oxide is 2.46g/cm³; the density of amorphous boron oxide is 1.80-1.84g/ cm³; melting point: 557℃; solubility (g/100gH_２O): 1.1(0℃), 15.7 (100℃). This product is quite water-absorable, which will become turbid state when it getting wet. It also can be dissolved in alcohol.
In low temperature, H₃BO₃ will generate crystalline boron trioxide after dehydration. This crystal contains BO₄ tetrahedral structural units; its density is 1.805g·cm^-3 ; melting point is 450℃. The density of glassy Boron Oxide is 1.795 g·cm^-3 ; it will gradually softening when temperature is getting up; and it will become liquid under high temperature condition; its boiling point is 1500℃. B₂O₃ will be available when boron compound with oxygen.