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Boron trioxide is produced by treating borax with sulfuric acid in a fusion furnace. At temperatures above 750 °C, the molten boron oxide layer separates out from sodium sulfate. It is then decanted, cooled and obtained in 96–97% purity. [3] Another method is heating boric acid above ~300 °C.
Borosilicate glass is a type of glass with silica and boron trioxide as the main glass-forming constituents. Borosilicate glasses are known for having very low coefficients of thermal expansion (≈3 × 10 −6 K −1 at 20 °C), making them more resistant to thermal shock than any other common glass. Such glass is subjected to less thermal ...
Dehydrated γ-barium borate can be prepared by heating to 300–400 °C. Calcination at about 600–800 °C causes complete conversion to the β form. BBO prepared by this method does not contain trace amounts of BaB 2 O 2 [8] BBO crystals for nonlinear optics can be grown from fluxed melt of barium borate, sodium oxide and sodium chloride. [9]
Boric acid, more specifically orthoboric acid, is a compound of boron, oxygen, and hydrogen with formula B(OH) 3. It may also be called hydrogen orthoborate, trihydroxidoboron or boracic acid. [3] It is usually encountered as colorless crystals or a white powder, that dissolves in water, and occurs in nature as the mineral sassolite.
Borax (also referred to as sodium borate, tincal (/ ˈtɪŋkəl /) and tincar (/ ˈtɪŋkər /)) is a salt (ionic compound), a hydrated or anhydrous borate of sodium, with the chemical formula Na 2 H 20 B 4 O 17 (also written as Na 2 B 4 O 7·10H2O[1][a]). It is a colorless crystalline solid that dissolves in water to make a basic solution.
The wurtzite form of boron nitride (w-BN; point group = C 6v; space group = P6 3 mc) has the same structure as lonsdaleite, a rare hexagonal polymorph of carbon. As in the cubic form, the boron and nitrogen atoms are grouped into tetrahedra. [6] In the wurtzite form, the boron and nitrogen atoms are grouped into 6-membered rings.
Allotropes of boron. Boron can be prepared in several crystalline and amorphous forms. Well known crystalline forms are α-rhombohedral (α-R), β-rhombohedral (β-R), and β-tetragonal (β-T). In special circumstances, boron can also be synthesized in the form of its α-tetragonal (α-T) and γ-orthorhombic (γ) allotropes.
Calcium borate (Ca 3 (BO 3) 2). It can be prepared by reacting calcium metal with boric acid. The resulting precipitate is calcium borate. A hydrated form occurs naturally as the minerals colemanite, nobleite and priceite. [citation needed] One of its uses is as a binder in some grades of hexagonal boron nitride for hot pressing.