Aluminum oxihydroxides

Two crystalline polymorphs of monohydrated alumina or aluminum oxihydroxide [A10(OH) = AI3O3.H3O], where the [AlO/ j octahedrons share one edge boe/imite [y-AIO(OH)] ... 

Table 10.3. Alumina hydrates (aluminum trihydroxides and oxihydroxides)...

While rain and soil solutions dissolve easily soluble ions such as K, Na, Ca, and Mg from the minerals of the parent rocks, the degree to which Fe, AP, and Si are attacked and solubilized depends to a large extent on the pH and Eh values of the leaching solutions. The environmental conditions determine also the degree of reprecipitation of hydroxides into the surrounding soil, in particular iron and aluminum hydroxides and oxihydroxides. Freely moving water and... 

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