In chemistry, metal hydroxides are a family of compounds of the form where M is a metal. They consist of hydroxide () anions and metallic cations, and are often strong bases. Some metal hydroxides, such as alkali metal hydroxides, ionize completely when dissolved. Certain metal hydroxides are weak electrolytes and dissolve only partially in aqueous solution.
Examples
Aluminium hydroxide
Beryllium hydroxide
Cobalt(II) hydroxide
Copper(II) hydroxide
Curium hydroxide
Gold(III) hydroxide
Iron(II) hydroxide
Mercury(II) hydroxide
Nickel(II) hydroxide
Tin(II) hydroxide
Uranyl hydroxide
Zinc hydroxide
Zirconium(IV) hydroxide
Lithium hydroxide
Rubidium hydroxide
Cesium hydroxide
Sodium hydroxide
Potassium hydroxide
Alkali metal hydroxides
Other metal hydroxides
Gallium(III) hydroxide
Lead(II) hydroxide
Thallium(I) hydroxide
Thallium(III) hydroxide
Role in soils
In soils, it is assumed that larger amounts of natural phenols are released from decomposing plant litter rather than from throughfall in any natural plant community. Decomposition of dead plant material causes complex organic compounds to be slowly oxidized (lignin-like humus) or to break down into simpler forms (sugars and amino sugars, aliphatic and phenolic organic acids), which are further transformed into microbial biomass (microbial humus) or are reorganized, and further oxidized, into humic assemblages (fulvic and humic acids), which bind to clay minerals and metal hydroxides.