Search results
Results from the WOW.Com Content Network
Aluminium hydroxide is amphoteric, i.e., it has both basic and acidic properties. Closely related are aluminium oxide hydroxide , AlO(OH), and aluminium oxide or alumina ( Al 2 O 3 ), the latter of which is also amphoteric.
Aluminium hydroxide oxide or aluminium oxyhydroxide, AlO(OH) is found as one of two well defined crystalline phases, which are also known as the minerals boehmite and diaspore. The minerals are important constituents of the aluminium ore , bauxite .
One third of the potential octahedral spaces are missing a central aluminium. The result is a neutral sheet: with aluminium as a +3 ion and hydroxide a −1 ion, the net cationic charge of one aluminium per six hydroxides is (+3)/6 = +1/2, and likewise the net anionic charge of one hydroxide per two aluminium atoms is (−1)/2 = −1/2.
Many metals (such as zinc, tin, lead, aluminium, and beryllium) form amphoteric oxides or hydroxides. Aluminium oxide (Al 2 O 3) is an example of an amphoteric oxide. Amphoterism depends on the oxidation states of the oxide. Amphoteric oxides include lead(II) oxide and zinc oxide, among many others. [2]
Activated alumina is manufactured from aluminium hydroxide by dehydroxylating it in a way that produces a highly porous material; this material can have a surface area significantly over 200 m 2 /g. The compound is used as a desiccant (to keep things dry by adsorbing water from the air) and as a filter of fluoride , arsenic and selenium in ...
Hydroxyaluminium(I), also known as Aluminium(I) hydroxide, is an inorganic chemical with molecular formula AlOH. It consists of aluminium in the +1 oxidation state paired with a single hydroxide . It has been detected as a molecular substance in the envelope of an oxygen -rich red supergiant star , a place where substances containing metals or ...
The solution, free of solids, is seeded with small crystals of aluminium hydroxide; this causes decomposition of the [Al(OH) 4] − ions to aluminium hydroxide. After about half of aluminium has precipitated, the mixture is sent to classifiers. Small crystals of aluminium hydroxide are collected to serve as seeding agents; coarse particles are ...
The process ends with precipitation of aluminium hydroxide, Al(OH) 3. This is useful for clarification of water, as the precipitate nucleates on suspended particles in the water, hence removing them. Increasing the pH even further leads to the hydroxide dissolving again as aluminate, [Al(H 2 O) 2 (OH) 4] −, is formed.