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Why are chlorine compounds with positive oxidation states often bonded to oxygen or fluorine?

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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.

Although chlorine has a high first ionization energy, it can exhibit positive oxidation states (+1, +3, +4, +5, +6, and +7) in various compounds. While these positive oxidation states are generally not very stable, they are effectively stabilized through coordination with oxygen or fluorine.12

In these specific compounds, the bonding is predominantly covalent. Because oxygen and fluorine are highly electronegative, they are well-suited to stabilize chlorine in these higher oxidation states through this covalent coordination. This stabilization allows chlorine to form a range of reactive species, such as oxyacids and various oxides, where the chlorine atom is joined to these electronegative partners.132