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Why can alkali metals react violently with water?

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A color-coded periodic table of the elements displays each element's symbol and atomic number, with categories such as alkali metals, noble gases, halogens, transition metals, and actinoid elements distinguished by different background colors. — alkali metal Modern version of the periodic table of the elements (printable).

Alkali metals react violently with water because they are highly reactive, a property stemming from their low ionization energy, which allows them to easily lose their single valence electron.123

When these metals come into contact with water, they undergo a chemical reaction represented by the equation:
$M + H_{2} O \to M O H + 1 / 2 H_{2}$

This process is highly exothermic, meaning it releases significant amounts of heat. The reaction generates hydrogen gas, which can subsequently react with oxygen, further increasing the heat produced. With small metal droplets or thin films, this rapid release of energy can lead to an explosion. The intensity of the reaction increases with the metal's atomic weight, as heavier alkali metals lose their valence electrons more easily. Additionally, because the resulting hydroxides of heavier alkali metals are highly soluble, they are quickly removed from the metal's surface, allowing the reaction to proceed with unabated vigor.13