Search results
Results from the WOW.Com Content Network
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.
The ratio of tellurate to borate reflects the degree of condensation. In [TeO 4 (BO 3) 2] 8-the anions are linked into a chain. [1] In [TeO 2 (BO 3) 4] 10− the structure is zero dimensional with isolated anions. These arrangements of oxygen around boron and tellurium can have forms resembling silicates. The first borotellurates to be ...
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]
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.
Ulexite is a borate mineral because its formula (NaCaB 5 O 6 (OH) 6 ·5H 2 O) contains boron and oxygen. The isolated borate polyanion [B 5 O 6 (OH) 6] 3− has five boron atoms, therefore placing ulexite in the pentaborate group. Ulexite is a structurally complex mineral, with a basic structure containing chains of sodium, water and hydroxide ...
Sodium borate is a generic name for any salt of sodium with an anion consisting of boron and oxygen, and possibly hydrogen, or any hydrate thereof. It can be seen as a hydrated sodium salt of the appropriate boroxy acid , although the latter may not be a stable compound.
The borate chlorides are chemical compounds that contain both borate ions and chloride ions. They are mixed anion compounds. Many of them are minerals.
Most of the white varieties of turquoise are chalk-like with a Mohs hardness of 1, and are not as hard or durable as howlite, and subsequently require stabilization in order to be used in jewelry, which has resulted in howlite being more popular for use in jewelry than the artificially stabilized white forms of the mineral turquoise.