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{{More sources|date=May 2020}}
The '''alkali hydroxides''' are a class of [[chemical compound]]s which are composed of an [[alkali metal]] [[cation]] and the [[hydroxide]] anion (
*[[Lithium hydroxide]] (LiOH)
*[[Sodium hydroxide]] (NaOH)
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*[[Rubidium hydroxide]] (RbOH)
*[[Caesium hydroxide]] (CsOH)
*[[Francium hydroxide]] (FrOH)
== Production ==
Alkali hydroxides are formed in the reaction between alkali metals and water. A typical school demonstration demonstrates what happens when a piece of an alkali metal is introduced to a bowl of water. A vigorous reaction occurs, producing [[hydrogen]] gas and the specific alkali hydroxide. For example, if sodium is the alkali metal:▼
:
[[Sodium hydroxide]] is an important industrial chemical, where it is produced by the [[chloralkali process]].
== Properties and uses ==
▲A typical school demonstration demonstrates what happens when a piece of an alkali metal is introduced to a bowl of water. A vigorous reaction occurs, producing [[hydrogen]] gas and the specific alkali hydroxide. For example, if sodium is the alkali metal:
The alkali metal hydroxides form white crystals that are [[hygroscopic]] and readily soluble in water, generating large amounts of heat upon dissolution. The solubility increases down the column as the alkali metal ions become larger and the lattice enthalpies decrease.<ref>{{cite journal|title=Solubility of Alkali Metal Chlorides and Hydroxides in Water|journal=Fiber Chemistry|volume=25|issue=6|date=1993|last=Skolunov|first=A. V.|doi=10.1007/BF00550787}}</ref>
All alkali metal hydroxides are [[strong base]]s, meaning that they dissociate completely in solution to give {{chem2|OH−}} ions. As strong bases, alkali hydroxides are highly corrosive and are used in [[cleaning product]]s. Sodium hydroxide is readily available in most hardware stores in products such as a [[drain cleaner]]. Similarly, potassium hydroxide is available as a solution used for cleaning terraces and other areas made out of wood. Both NaOH and KOH are also used in the production of soap and detergents ([[saponification]]).
▲:Sodium + water → sodium hydroxide + hydrogen gas
Due to their hygroscopic properties, alkali hydroxides are used as [[desiccant]]s. They also readily absorb carbon dioxide and are therefore used in [[carbon dioxide scrubber]]s.<ref>{{cite book|last=Breuer|first=D.|last2=Heinrich|first2=B.|title=The MAK‐Collection for Occupational Health and Safety: Annual Thresholds and Classifications for the Workplace|chapter=hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide) [Air Monitoring Methods, 2003]|date=2003|doi=10.1002/3527600418.am131065e0008}}</ref>
== Notes ==▼
*[[Hydroperoxide]], a peroxide analog of hydroxide
*[[Hydrosulfide]], a sulfur analog of hydroxide
*[[Sodium hydroselenide|Hydroselenide]], a selenium analog of hydroxide
*[[Azanide]], a nitrogen analog of hydroxide
*[[Phosphanide]], a phosphorus analog of hydroxide and azanide
*[[Arsanide]], an arsenic analog of hydroxide and azanide
== References ==
{{reflist}}
[[Category:Hydroxides]]
[[Category:Alkali metals]]
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