Metal hydroxides are

hydroxide Hydroxide is a diatomic anion with chemical formula OH−. It consists of an oxygen and hydrogen atom held together by a single covalent bond, and carries a negative electric charge. It is an important but usually minor constituent of water. I ...

s of

metal A metal (from Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typicall ...

s. They are often strong bases. They consist of

anions and metallic

cation An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convent ...

s. 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 Aluminium hydroxide, Al(OH)3, is found in nature as the mineral gibbsite (also known as hydrargillite) and its three much rarer polymorphs: bayerite, doyleite, and nordstrandite. Aluminium hydroxide is amphoteric, i.e., it has both basic and ...

Beryllium hydroxide Beryllium hydroxide, Be(OH)2, is an amphoteric hydroxide, dissolving in both acids and alkalis. Industrially, it is produced as a by-product in the extraction of beryllium metal from the ores beryl and bertrandite. The natural pure beryllium hydro ...

Cobalt(II) hydroxide Cobalt(II) hydroxide or cobaltous hydroxide is the inorganic compound with the formula , consisting of divalent cobalt cations and hydroxide anions . The pure compound, often called the "beta form" (β-) is a pink solid insoluble in water. The n ...

Copper(II) hydroxide Copper(II) hydroxide is the hydroxide of copper with the chemical formula of Cu(OH)2. It is a pale greenish blue or bluish green solid. Some forms of copper(II) hydroxide are sold as "stabilized" copper(II) hydroxide, although they likely consist ...

* Curium hydroxide *

Gold(III) hydroxide Gold(III) hydroxide, gold trihydroxide, or gold hydroxide is an inorganic compound, a hydroxide of gold, with formula Au(OH)3. It is also called auric acid with formula H3AuO3. It is easily dehydrated above 140 °C to gold(III) oxide. Salts ...

Iron(II) hydroxide Iron(II) hydroxide or ferrous hydroxide is an inorganic compound with the formula Fe(OH)2. It is produced when iron(II) salts, from a compound such as iron(II) sulfate, are treated with hydroxide ions. Iron(II) hydroxide is a white solid, but ev ...

* Mercury(II) hydroxide *

Nickel(II) hydroxide Nickel(II) hydroxide is the inorganic compound with the formula Ni(OH)2. It is an apple-green solid that dissolves with decomposition in ammonia and amines and is attacked by acids. It is electroactive, being converted to the Ni(III) oxy-hydrox ...

Tin(II) hydroxide Tin(II) hydroxide, Sn(OH)2, also known as ''stannous hydroxide'', is an inorganic compound tin(II). The only related material for which definitive information is available is the oxy hydroxide Sn6O4(OH)4, but other related materials are claimed. ...

Uranyl hydroxide Uranyl hydroxide is a hydroxide of uranium with the chemical formula UO2(OH)2 in the monomeric form and (UO2)2(OH)4 in the dimeric; both forms may exist in normal aqueous media. Uranyl hydroxide hydrate is precipitated as a colloidal yellowcake f ...

Zinc hydroxide Zinc hydroxide Zn( OH)2 is an inorganic chemical compound. It also occurs naturally as 3 rare minerals: wülfingite (orthorhombic), ashoverite and sweetite (both tetragonal). Like the hydroxides of other metals, such as lead, aluminium, beryll ...

* Zirconium(IV) hydroxide *

Lithium hydroxide Lithium hydroxide is an inorganic compound with the formula LiOH. It can exist as anhydrous or hydrated, and both forms are white hygroscopic solids. They are soluble in water and slightly soluble in ethanol. Both are available commercially. While ...

Rubidium hydroxide Rubidium hydroxide is the inorganic compound with the formula RbOH. It consists of rubidium cations and an equal number of hydroxide anions. It is a colorless solid that is commercially available as aqueous solutions from a few suppliers. Like ot ...

Cesium hydroxide Caesium hydroxide is a strong base (pKa= 15.76) containing the highly reactive alkali metal caesium, much like the other alkali metal hydroxides such as sodium hydroxide and potassium hydroxide. Caesium hydroxide is corrosive enough to quick ...

Sodium hydroxide Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly caustic base and alkali ...

Potassium hydroxide Potassium hydroxide is an inorganic compound with the formula K OH, and is commonly called caustic potash. Along with sodium hydroxide (NaOH), KOH is a prototypical strong base. It has many industrial and niche applications, most of which exp ...

Alkali metal hydroxides

Other metal hydroxides

Gallium(III) hydroxide Gallium hydroxide, Ga(OH)3 is formed as a gel following the addition of ammonia to Ga3+ salts.Anthony John Downs, (1993), ''Chemistry of Aluminium, Gallium, Indium, and Thallium'', Springer, It is also found in nature as the rare mineral söhngei ...

Lead(II) hydroxide Lead(II) hydroxide, Pb(OH)2, is a hydroxide of lead, with lead in oxidation state +2. In 1964 it was believed that such a simple compound did not exist, as lead basic carbonate (2PbCO3·Pb(OH)2) or lead(II) oxide (PbO) was encountered where lead ...

Thallium(I) hydroxide Thallium(I) hydroxide, also called thallous hydroxide, TlOH, is a hydroxide of thallium, with thallium in oxidation state +1. Synthesis Thallium(I) hydroxide is obtained from the decomposition of thallium(I) ethoxide in water. :C2H5OTl + H2O � ...

Thallium(III) hydroxide Thallium(III) hydroxide, , also known as thallic hydroxide, is a hydroxide of thallium. It is a white solid. Thallium(III) hydroxide is a very weak base; it dissociates to give the thallium(III) ion An ion () is an atom or molecule with a n ...

Role in soils

soil Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...

s, it is assumed that larger amounts of

natural phenol In biochemistry, naturally occurring phenols are natural products containing at least one phenol functional group. Phenolic compounds are produced by plants and microorganisms. Organisms sometimes synthesize phenolic compounds in response to eco ...

s are released from decomposing

plant litter Plant litter (also leaf litter, tree litter, soil litter, litterfall or duff) is dead plant material (such as leaves, bark, needles, twigs, and cladodes) that have fallen to the ground. This detritus or dead organic material and its constituent ...

rather than from throughfall in any natural plant community. Decomposition of dead plant material causes complex organic compounds to be slowly oxidized (

lignin Lignin is a class of complex organic polymers that form key structural materials in the support tissues of most plants. Lignins are particularly important in the formation of cell walls, especially in wood and bark, because they lend rigidity ...

-like

humus In classical soil science, humus is the dark organic matter in soil that is formed by the decomposition of plant and animal matter. It is a kind of soil organic matter. It is rich in nutrients and retains moisture in the soil. Humus is the Lati ...

) 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 Humic substances (HS) are organic compounds that are important components of humus, the major organic fraction of soil, peat, and coal (and also a constituent of many upland streams, dystrophic lakes, and ocean water). For a long era in the 19th an ...

acids), which bind to

clay mineral Clay minerals are hydrous aluminium phyllosilicates (e.g. kaolin, Al2 Si2 O5( OH)4), sometimes with variable amounts of iron, magnesium, alkali metals, alkaline earths, and other cations found on or near some planetary surfaces. Clay minerals ...

s and metal hydroxides.

References

Metals Hydroxides {{Chemistry-stub