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How does chlorine react with water to form chlorine water?

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A labeled diagram of the chlorine element from the periodic table shows its atomic number 17, symbol Cl, electron configuration, and atomic weight range. The box is shaded green to indicate chlorine is a halogen, with icons for orthorhombic crystal structure, gas state at room temperature, and strong acidity. A key explains the icons and colors used. — chlorine Properties of chlorine.

Chlorine is moderately soluble in water, and this process yields a solution known as chlorine water.1

When chlorine gas dissolves in water, it undergoes a chemical reaction that results in the formation of both hydrochloric acid and hypochlorous acid. This reaction is a form of disproportionation, where one chlorine atom is oxidized and another is reduced, as represented by the following chemical equation:

$C l_{2} + H_{2} O ⇌ H O C l + H C l$

In this process, the solution becomes acidic. Chlorine water is characterized as a yellowish aqueous solution that functions as an oxidizing agent, though its effectiveness in this capacity diminishes over time as the unstable hypochlorous acid gradually decomposes. Additionally, when this solution stands, a solid hydrate can be obtained, which features a structure more open than that of ice.123