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The Borate Minerals are minerals which contain a borate anion group. The borate (BO 3) units may be polymerised similar to the SiO 4 unit of the silicate mineral class. This results in B 2 O 5, B 3 O 6, B 2 O 4 anions as well as more complex structures which include hydroxide or halogen anions. [2] The [B(O,OH) 4] − anion exists as well.
Borate ions occur, alone or with other anions, in many borate and borosilicate minerals such as borax, boracite, ulexite (boronatrocalcite) and colemanite. Borates also occur in seawater, where they make an important contribution to the absorption of low frequency sound in seawater. [1] Borates also occur in plants, including almost all fruits. [2]
Trimethyl borate is a popular borate ester used in organic synthesis. Borate esters form spontaneously when treated with diols such as sugars and the reaction with mannitol forms the basis of a titrimetric analytical method for boric acid. Metaborate esters show considerable Lewis acidity and can initiate epoxide polymerization reactions. [4]
It catalyzes formation of char and creates a protective layer of glass. Zinc catalyzes the release of halogens by forming zinc halides and zinc oxyhalides. In halogen-free system, zinc borate can be used together with alumina trihydrate, magnesium hydroxide, red phosphorus, or ammonium polyphosphate. During burning the plastics, a porous borate ...
Unlike silicates, boron minerals never contain boron with coordination number greater than four. A typical motif is exemplified by the tetraborate anions of the common mineral borax, shown at left. The formal negative charge of the tetrahedral borate center is balanced by metal cations in the minerals, such as the sodium (Na +) in borax. [1]
An important synthetic application using such dialkylboranes, such as diethylborane, is the transmetallation of the organoboron compounds to form organozinc compounds. [9] [10] Some diaryl and dialkylboranes are well known. Dimesitylborane is a dimer (C 6 H 2 Me 3) 4 B 2 H 2). It reacts only slowly with simple terminal alkenes.
Disodium octaborate is a borate of sodium, a chemical compound of sodium, boron, and oxygen — a salt with elemental formula Na 2 B 8 O 13 or (Na +) 2 [B 8 O 13] 2−, also written as Na 2 O·4B 2 O 3. It is a colorless crystalline solid, soluble in water.
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.