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How does chlorine displace iodine from iodide compounds?

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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 displaces iodine from iodide compounds because it is a stronger oxidizing agent than iodine. In this chemical process, chlorine atoms attract electrons more effectively than iodine atoms, allowing chlorine to replace the iodide ions in their compounds.1234

When elemental chlorine (Cl $_{2}$ ) is added to a solution containing iodide ions (I $^{-}$ ), the chlorine is reduced to chloride ions (Cl $^{-}$ ), while the iodide ions are oxidized to free elemental iodine (I $_{2}$ ). This displacement reaction is a standard method used in analytical chemistry to detect the presence of iodide ions, as the formation of free iodine can be identified by its characteristic color or by using a starch indicator, which turns bright blue in the presence of iodine.456

Generally, within the halogen family, any element can displace those that are less electronegative and lower in the group from their compounds. Consequently, chlorine is capable of replacing bromide, iodide, and astatide ions.34