Boron oxide: 99% 30um

It is a colorless glassy crystal or powder. Hard and brittle, the surface is smooth and odorless. It is stable to heat, and it is not reduced by carbon when it is white, but alkali metal and magnesium and aluminum can be reduced to monomer boron. At about 600 ° C, it becomes a highly viscous liquid. The boric anhydride absorbs strongly in air to form boric acid. Soluble in acid, ethanol, hot water, slightly soluble in cold water. Boron oxide can be combined with several metal oxides to form a borosilicate glass having a characteristic color. It is completely miscible with alkali metal, copper, silver, lead, arsenic, antimony and antimony oxides.

The density of crystalline boron oxide is 2.46 g/cm3, the density of amorphous boron oxide is 1.80-1.84 g/cm3, melting point: 557 ° C, solubility: (g/100 gH2O): 1.1 (0 ° C), 15.7 (100 ° C) It is very easy to absorb water, becomes turbid after moisture absorption, and is also soluble in alcohol.

At a lower temperature, H3BO3 is dehydrated to obtain crystals of boron trioxide. This crystal contains a BO4 tetrahedral structural unit having a density of 1.805 g·cm-3 and a melting point of 450 °C. The glassy boron oxide has a density of 1.795 g·cm -3 and gradually softens when the temperature rises. When it reaches the high temperature of red heat, it becomes liquid and has a boiling point of 1500 ° C. Boron is directly combined with oxygen to obtain B2O3.