Aluminate
Encyclopedia
An aluminate is a compound containing aluminium
and oxygen
. When precipitated from solution, the anion condenses with more electropositive elements. The generally accepted form of the aluminate is a mononuclear tetrahedral complex that is negatively charged, Al(OH)4− or AlO2−. Examples of aluminate compounds include sodium aluminate
(Na2Al2O4) and potassium aluminate
(K2Al2O4), both being alkali-ion precipitates of the tetrahedral monomer obtained from an alkaline solution. Aluminate can also refer to the polyatomic ion .
Since aluminum is closer to the nonmetals, it has some nonmetal characteristics and some metal characteristics. Its oxide is amphoteric: it dissolves in both bases and acids. When dissolved in bases it forms the aluminate ion. An aluminate can be considered as the neutralization of aluminum oxide with a base, or an adduct of aluminum oxide with the base.
Minerals like chrysoberyl
are sometimes called aluminates, although they are usually classified as mixed oxide
s. As minerals, aluminates are much less common than aluminosilicate
s.
See :Category:Aluminates for a list of aluminates.
and fluorescent ions. Aerodynamic levitation
is a key method used to study and produce many aluminate glasses. Levitation allows high purity to be maintained in the melt at temperatures in excess of 2000K.
Some materials that are known to form glass in binary combination with aluminium oxide are: rare earth oxides, alkaline earth oxides (CaO, SrO, BaO)
lead oxide, and silicon dioxide.
Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
and oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
. When precipitated from solution, the anion condenses with more electropositive elements. The generally accepted form of the aluminate is a mononuclear tetrahedral complex that is negatively charged, Al(OH)4− or AlO2−. Examples of aluminate compounds include sodium aluminate
Sodium aluminate
Sodium aluminate is an important commercial inorganic chemical. It works as an effective source of aluminium hydroxide for many industrial and technical applications. Pure sodium aluminate is a white crystalline solid having a formula variously given as NaAlO2, NaAl4 , Na2O·Al2O3, or Na2Al2O4...
(Na2Al2O4) and potassium aluminate
Potassium aluminate
Potassium aluminate is an inorganic compound with the formula . It is used as a dyeing and printing mordant, as a paper sizing, as an accelerant in the setting of concrete....
(K2Al2O4), both being alkali-ion precipitates of the tetrahedral monomer obtained from an alkaline solution. Aluminate can also refer to the polyatomic ion .
Since aluminum is closer to the nonmetals, it has some nonmetal characteristics and some metal characteristics. Its oxide is amphoteric: it dissolves in both bases and acids. When dissolved in bases it forms the aluminate ion. An aluminate can be considered as the neutralization of aluminum oxide with a base, or an adduct of aluminum oxide with the base.
Minerals like chrysoberyl
Chrysoberyl
The mineral or gemstone chrysoberyl is an aluminate of beryllium with the formula BeAl2O4. The name chrysoberyl is derived from the Greek words χρυσός chrysos and βήρυλλος beryllos, meaning "a gold-white spar". Despite the similarity of their names, chrysoberyl and beryl are two completely...
are sometimes called aluminates, although they are usually classified as mixed oxide
Mixed oxide
In chemistry, a mixed oxide is a somewhat informal name for an oxide that contains more than one chemical element in its cation, or of a single element cation that has atoms in several states of oxidation....
s. As minerals, aluminates are much less common than aluminosilicate
Aluminosilicate
Aluminosilicate minerals are minerals composed of aluminium, silicon, and oxygen, plus countercations. They are a major component of kaolin and other clay minerals....
s.
See :Category:Aluminates for a list of aluminates.
Aluminate glasses
Alumina on its own cannot easily be made glassy with current techniques, however with the addition of a second compound many types of aluminate glasses can be formed. The glasses produced display a range of interesting and useful properties, such as high refractive index, good infra red transparency, and high melting point, as well as the ability to host laser activeActive laser medium
The active laser medium is the source of optical gain within a laser. The gain results from the stimulated emission of electronic or molecular transitions to a lower energy state from a higher energy state...
and fluorescent ions. Aerodynamic levitation
Aerodynamic levitation
Aerodynamic levitation is the use of gas pressure to levitate materials so that they are no longer in physical contact with any container. In scientific experiments this removes contamination and nucleation issues associated with physical contact with a container.-Overview:The term aerodynamic...
is a key method used to study and produce many aluminate glasses. Levitation allows high purity to be maintained in the melt at temperatures in excess of 2000K.
Some materials that are known to form glass in binary combination with aluminium oxide are: rare earth oxides, alkaline earth oxides (CaO, SrO, BaO)
lead oxide, and silicon dioxide.