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*[[Sodium Hydroxide]]
*[[Potassium Hydroxide]]
==Key Stage 4==
===Meaning===
An [[alkali]] is [[base|basic]] [[compound]] which [[dissolve]]s in [[water]] to form [[Hydroxide Ion|OH<sup>-</sup> ions]] making a [[solution]] with [[pH]] greater than [[Neutral (Chemistry)|7]].
===About Alkalis===
: [[Alkali]]s are [[base]]s in [[solution]] which form [[Hydroxide Ion|Hydroxide ions]].
: When a [[base]]ic [[compound]] [[dissolve]]s in [[water]] a [[Hydroxide Ion|Hydroxide ion]] becomes dissociated from either the [[base|basic]] [[compound]] or from a [[water]] [[molecule]]. That [[Hydroxide Ion|Hydroxide ion]] is free to move separately in the [[solution]].
: The [[Hydroxide Ion|Hydroxide ion]]s in an [[alkali]] will donate [[electron]]s to [[Hydrogen Ion|Hydrogen ions]] to form [[water]]. This is a [[neutralisation]] [[Chemical Reaction|reaction]].
: The strength of an [[alkali]] is measured on the [[pH]] scale. The more [[Hydroxide Ion|Hydroxide ions]] in a [[solution]] the lower the [[pH]].