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How does chlorine displace bromine from bromide 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 bromine from bromide compounds through a chemical process known as displacement or oxidation. Because chlorine is a more powerful oxidizing agent than bromine, it can effectively remove electrons from bromide ions ( $B r^{-}$ ) in a solution, converting them into elemental bromine ( $B r_{2}$ ) while the chlorine itself is reduced to chloride ions ( $C l^{-}$ ).12

This principle is utilized industrially to extract bromine from ocean water. In this process, chlorine is added to the water, which contains dissolved bromide ions, to trigger the oxidation reaction. The resulting free bromine can then be separated from the solution.1

This reactivity follows the general trend among halogens, where lighter, more electronegative halogens are capable of displacing heavier halide ions from their compounds. Specifically, while fluorine can displace any other halide ion, chlorine is limited to displacing bromide, iodide, and astatide ions.2