Final answer:
True. Potassium, rubidium, and cesium can form compounds that contain the superoxide ion (O₂¹⁻). Examples of superoxides include KO₂, RbO₂, and CsO₂, which are formed when these metals react with excess oxygen.
Step-by-step explanation:
True. Potassium, rubidium, and cesium can all form compounds that contain the superoxide ion (O₂¹⁻). Superoxides are compounds in which the oxygen atom has a charge of -1/2.
Examples of superoxides include KO₂, RbO₂, and CsO₂, which are formed when these metals react with excess oxygen.