Boric Acid

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Boric Acid, white crystalline powder. Although boric acid is poorly soluble in water at room temperature (1 g dissolving in 18 g water), it dissolves readily in hot water (1 g dissolving in less than 4 g water) and in alcohol and glycerine. It is slightly volatile in steam. A significant amount of boric acid appears in natural steam vents in Tuscany (Toscana), Italy, but free boric acid is not otherwise found in nature. Salts, however, occur in many places. Boric acid can be easily prepared by treating borax with sulfuric acid. Boric acid in solution is only slightly acidic and acts as a nonirritating, slightly astringent antiseptic, mild enough to be used as an eyewash. Commercially, boric acid is used in glazing pottery, in fireproofing cloth, in making electroplating baths and artificial gems, and in hardening steels.

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