- Differences in physical properties:
Borax is colorless translucent crystal or white crystalline powder. Odorless, salty.
Boric acid is white powder crystal or triclinic axial scale-like luster crystal, with smooth feel and no odor.
2, the difference in chemical shape:
Borax soluble in water, glycerin, slightly soluble in alcohol. The aqueous solution is weakly alkaline. Borax can be slowly weathered in air. When melted, it forms a colorless glassy substance
Boric acid is dissolved in water, alcohol, glycerin, ethers and essential oils, and the aqueous solution is weakly acidic. The solubility of boric acid in water increases with the increase of temperature, and can volatilize with water vapor. It is less soluble in inorganic acids than in water. When heated to 70 ~ 100℃, metaborate is gradually dehydrated to form metaborate, pyroboric acid is formed at 150 ~ 160℃, and boric anhydride (B2O3) is formed at 300℃.
3, the difference in use:
The main uses of borax are: 1 in glass, it can enhance the transmission of ultraviolet light, improve the transparency and heat resistance of glass; 2 in enamel products, it can make the glaze not easy to fall off and make it shiny. 3 Rust remover for metal surface. Borax at 878℃ high temperature, will melt into a glass, the melt contains acid oxide B2O3, so it can dissolve the metal surface oxide. It is mainly used to remove oxides from metal surfaces when welding metal.