Final answer:
Alkali metals react with water to produce hydrogen gas and a basic solution of metal hydroxide, forming strong bases that completely dissociate in water, releasing hydroxide ions.
Step-by-step explanation:
Alkali metals react with water to produce hydrogen gas and a basic solution of the metal hydroxide, therefore forming strong bases. For example, when lithium reacts with water, the equation is 2Li(s) + 2H₂O(l) → 2LiOH(aq) + H₂(g). This vigorous reaction suggests alkali metals are easier to oxidize than hydrogen. Strong bases, such as the hydroxides of alkali metals (LiOH, NaOH, KOH, RbOH, and CSOH), are known to dissociate completely in water, providing a high concentration of hydroxide ions (OH⁻).
Similarly, other group 1 and 2 metals, excluding beryllium and magnesium, also react with water to form hydroxides and hydrogen gas. For instance, calcium reacts with water according to the equation: Ca(s) + 2H₂O(l) → Ca(OH)₂(aq) + H₂(g). Such reactions underline strong bases' capacity to dissolve in water and dissociate into their constituent ions, thus contributing to strong basic solutions.